US7794972B2 - Benzoate-and anthranilate-inducible promoters - Google Patents
Benzoate-and anthranilate-inducible promoters Download PDFInfo
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- US7794972B2 US7794972B2 US11/028,156 US2815605A US7794972B2 US 7794972 B2 US7794972 B2 US 7794972B2 US 2815605 A US2815605 A US 2815605A US 7794972 B2 US7794972 B2 US 7794972B2
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- C—CHEMISTRY; METALLURGY
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- C07K—PEPTIDES
- C07K14/00—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
- C07K14/195—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from bacteria
- C07K14/21—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from bacteria from Pseudomonadaceae (F)
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- C12N15/00—Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
- C12N15/09—Recombinant DNA-technology
- C12N15/63—Introduction of foreign genetic material using vectors; Vectors; Use of hosts therefor; Regulation of expression
- C12N15/74—Vectors or expression systems specially adapted for prokaryotic hosts other than E. coli, e.g. Lactobacillus, Micromonospora
- C12N15/78—Vectors or expression systems specially adapted for prokaryotic hosts other than E. coli, e.g. Lactobacillus, Micromonospora for Pseudomonas
Definitions
- sequence listing is submitted electronically via EFS-Web as an ASCII formatted sequence listing with a file named “344269 SequenceListing.txt”, created on Jul. 31, 2009, and having a size of 86 kilobytes and is filed as an Amendment to the specification on Jul. 31, 2009.
- sequence listing contained in this ASCII formatted document is part of the specification and is herein incorporated by reference in its entirety.
- Gene expression in bacteria requires that a promoter be present in the regulatory region located 5′ (i.e. upstream) from the coding sequence in order to direct the gene's transcription.
- Promoters are classified as constitutive promoters and regulated promoters.
- regulated promoters have proven particularly useful because they permit increase in the organismal biomass while a desired gene(s) is inactive. This allows the host organism to devote maximal energy to cell division and growth. When the regulated promoter is then activated/induced, more cells will be available to express the desired gene(s), thereby increasing the yield of the desired gene product(s).
- Regulated promoters include: (1) activatable promoters, i.e. promoters that are inactive until an activator protein binds to the 5′ regulatory region; and (2) repressible promoters, i.e. promoters that are inactive while the 5′ regulatory region is bound by a repressor protein. Some genes or operons are regulated by more than one mechanism.
- Catabolite repression also called “glucose catabolite repression” or “carbon catabolite repression,” is a phenomenon in which gene(s) under the control of a regulated promoter are also maintained in an unexpressed state until the concentration of glucose (the primary carbon source) falls below a threshold level, e.g., until conditions of glucose starvation. In other words, such a gene(s) cannot be expressed until two conditions are met: 1) glucose reduction/starvation and 2) activation or derepression of the regulated promoter.
- the promoter selected for use in expressing the transgene of interest should have the following qualities. It should:
- lac promoter i.e. the lacZ promoter
- tac and trc promoters described in U.S. Pat. No. 4,551,433 to DeBoer, and the related promoters listed in
- the host cell contains a construct in which a tac promoter is operably attached to a gene or operon whose expression is desired.
- the lacI gene which is a constitutively expressed gene that encodes the Lac repressor protein which binds to the lac operator, is also included in the bacterial host cell (multiple copies of the lacI gene are usually included therein).
- an inducer is added to the culture in order to derepress the tac promoter and permit expression of the desired gene or operon.
- IPTG isopropyl- ⁇ -D-1-thiogalactopyranoside, also called “isopropylthiogalactoside”
- IPTG isopropyl- ⁇ -D-1-thiogalactopyranoside
- Standard IPTG preparations are currently available at about US$18 per gram or about US$125 per 10 grams; these IPTG preparations also contain dioxane, which is likewise toxic to biological systems.
- Dioxane-free IPTG is also available on the market, but costs about twice the price of standard IPTG (i.e. currently about US$36 per gram or about US$250 per 10 grams).
- lac promoters and their derivatives are “leaky” in that, even in a native, repressed state, the promoter permits a relatively high background level of expression. Therefore, multiple copies of the LacI repressor protein gene are usually included within the expression host cell in order to increase the degree of repression of the lac-type promoter. As a result, there is a need for promoters that are both useful for commercial fermentation systems and readily susceptible of being tightly controlled in an inactive state until induced.
- promoters induced by high temperatures are problematic: since high temperatures can be harmful to the host cell culture; since it is often impractical to generate an even temperature spike throughout the large-scale, commercial fermentation volume; and since it is preferred to operate commercial fermentation equipment at lower temperatures than required for such induction.
- the other four suggested promoters listed in Table 2 have, to the inventors' knowledge, not been demonstrated to function well in large-scale fermentation conditions; also, the alkyl- and halo-toluene inducers of the Pu promoter are significantly toxic to biological systems.
- promoters for use in commercial fermentation systems should be tightly regulated so that expression occurs only upon induction, preferably effected late in the fermentation run.
- the chemicals used to induce the promoters must be low cost, low-toxicity to the host bacterium and other organisms, and must tightly regulate gene expression.
- novel promoters that are tightly regulated and are induced at low cost using low-toxicity inducers.
- the present invention provides novel promoters that are useful for gene expression in commercial fermentation.
- the invention provides benzoate-inducible promoters, anthranilate-inducible promoters, and tandem promoters that may be employed in bacterial commercial fermentation systems.
- the present invention provides:
- isolated and/or recombinant benzoate promoter nucleic acids comprising the ⁇ 35 region of the Pseudomonas fluorescens native benzoate promoter attached upstream of the ⁇ 10 region thereof, via a 15-20 nucleotide linker; and to the operative promoter nucleic acid segment(s) found in SEQ ID NO:1;
- Such promoter nucleic acids further comprising a benzoate promoter activator protein (BenR) binding site; and
- Such promoter nucleic acids further comprising a benzoate promoter activator protein coding sequence, and where such activator protein coding sequences encode a benzoate promoter activator protein having an amino acid sequence at least 90% homologous to any one of the native, mutant, and/or truncated activator protein amino acids sequences presented in SEQ ID NO:2.
- the present invention also provides:
- anthranilate promoter nucleic acids comprising the ⁇ 35 region of the Pseudomonas fluorescens native anthranilate promoter attached upstream of the ⁇ 10 region thereof, via a 15-20 nucleotide linker; and to the operative promoter nucleic acid segment(s) found in SEQ ID NO:7;
- Such promoter nucleic acids further comprising an anthranilate promoter activator protein (AntR) binding site; and
- such promoter nucleic acids further comprising a anthranilate promoter activator protein coding sequence, and where such activator protein coding sequences encode an anthranilate promoter activator protein having an amino acid sequence at least 90% homologous to any one of the native, mutant, and/or truncated activator protein amino acids sequences presented in SEQ ID NO:9.
- the present invention also provides:
- tandem promoters comprising a non-catabolite-repressed promoter attached (i.e. covalently attached) to and upstream of a natively catabolite-repressed promoter, either directly or by means of an inter-promoter polynucleotide linker, in which the catabolite repression of the latter promoter is overcome and/or a different improved promoter property is exhibited;
- tandem promoters prepared by a process comprising covalently attaching a prokaryotic non-catabolite-repressed promoter to and upstream of a prokaryotic natively catabolite-repressed promoter, either directly or by means of an inter-promoter polynucleotide linker;
- inter-promoter polynucleotide linker is about 100 or less than 100 nucleotides long;
- tandem promoters in which the component non-catabolite-repressed and natively catabolite-repressed promoters are prokaryotic promoters, or bacterial promoters; and to tandem promoters in which the component promoters are obtained from the same of different species of the Pseudomonads and closely related bacteria, and/or of the genus Pseudomonas , and/or from Pseudomonas fluorescens ; and to tandem promoters in which the component promoters are obtained from gene(s) or operon(s) encoding alternative carbon source utilization enzyme(s) or pathway(s); and to tandem promoters in which the non-catabolite-repressed promoter is obtained from an operon encoding an anthranilate degradation pathway and the natively catabolite-repressed promoter is obtained from an operon encoding a benzoate degradation pathway, and/or in which the anthranilate promoter and benzoate promoter are selected from among those summarized in the above
- the present invention also provides:
- altered promoters prepared by a process comprising obtaining at least one polynucleotide having a base sequence at least 90% identical to and heterologous to the base sequence of any one of the claimed promoters or the sequence of any one of at least bases 1275-1307 of SEQ ID NO:1, at least bases 1239-1274 of SEQ ID NO:7, and at least bases 1329-1509 of SEQ ID NO:13; screening the polynucleotide(s) for the ability to direct transcription in a prokaryotic host cell, and optionally for at least one promoter property; and identifying, based on the results, at least one promoter, optionally having at least one improved property; and
- improved promoters prepared by a process of: utilizing a promoter polynucleotide, having a base sequence of any one of the claimed promoters or the sequence of any one of at least bases 1275-1307 of SEQ ID NO:1, at least bases 1239-1274 of SEQ ID NO:7, and at least bases 1329-1509 of SEQ ID NO:13, as a hybridization probe for sequence-altered polynucleotide(s) at least 90% homologous thereto, or of performing mutagenesis and/or recombination upon said promoter polynucleotide to generate said sequence-altered polynucleotide(s), or of utilizing an information string representing the base sequence of the promoter polynucleotide to perform a search for a heterologous string at least 90% homologous thereto and providing a sequence-altered polynucleotide having the base sequence represented by said heterologous string; or of modifying such an information string into such a heterologous string and utilizing said modified
- the present invention also provides:
- isolated nucleic acid molecules comprising a nucleic acid sequence whose complement hybridizes under stringent hybridization and wash conditions to a nucleobase polymer molecule having a base sequence of any one of the claimed promoters or of any one of at least bases 1275-13b7 of SEQ ID NO:1, at least bases 1239-1274 of SEQ ID NO:7, and at least bases 1329-1509 of SEQ ID NO:13, wherein said isolated nucleic acid molecule can function as a promoter in a prokaryotic cell; and
- nucleobase polymer molecules having the base sequence of a prokaryotic promoter polynucleotide molecule having a base sequence at least 90% identical to the base sequence of any one of the claimed promoters or of any one of at least bases 1275-1307 of SEQ ID NO:1, at least bases 1239-1274 of SEQ ID NO:7, and at least bases 1329-1509 of SEQ ID NO:13
- the present invention also provides:
- recombinant nucleic acid molecules that can function as expression construct(s) in a prokaryotic cell, comprising a promoter containing a base sequence at least 90% identical to the base sequence of any one of the claimed promoters or of any one of at least bases 1275-1307 of SEQ ID NO:1, at least bases 1239-1274 of SEQ ID NO:7, and at least bases 1329-1509 of SEQ ID NO:13; such recombinant expression constructs comprising an mRNA-encoding sequence; such recombinant expression constructs wherein the expression construct is a vector; such recombinant expression constructs wherein the vector is a plasmid; genetically engineered prokaryotic host cells containing any such a recombinant expression construct, and preferably also at least one, and more preferably more than one, copy of a gene encoding the relevant activator protein for the promoter of said recombinant expression construct (and where said gene is expressed in the host cell); expression systems comprising such a genetically
- the present invention also provides:
- a process for preparing a transcription product comprising growing such a genetically engineered prokaryotic host cell, and inducing the recombinant expression construct therein, thereby expressing the transcription product encoded thereby; and a process for preparing a polypeptide comprising expressing an mRNA transcription product, by use of such a process for preparing a transcription product, and further permitting the host cell to translate the mRNA into the polypeptide encoded thereby.
- the present invention also provides transcriptional activator proteins operative in prokaryotic cells. These include a transcriptional activator protein having an amino acid sequence at least 90% homologous to that of any one of residues 1-335 of SEQ ID NO:2, residues 1-335 of SEQ ID NO:2containing Asn152, residues 21-335 of SEQ ID NO:2, and residues 21-335 of SEQ ID NO:2 containing Asn152; and a transcriptional activator protein having an amino acid sequence at least 90% homologous to that of any one of residues 1-330 of SEQ ID NO:9, or of residues 1-330 of SEQ ID NO:9 containing Ala268.
- the present invention also provides polynucleotide molecules containing a base sequence encoding such transcriptional activator proteins.
- FIG. 1 presents a plasmid map of pDOW1019, a vector comprising Pben509, a benzoate-inducible promoter according to the present invention.
- FIG. 2 presents a plasmid map of pDOW1028, a vector comprising Pben278, a benzoate-inducible promoter according to the present invention.
- FIG. 3 presents a plasmid map of pDOW1035, a vector comprising an anthranilate-inducible promoter according to the present invention, including the coding sequence of the activator protein therefor.
- FIG. 4 presents a plasmid map of pDOW1057, a vector comprising an anthranilate-benzoate tandem promoter according to the present invention.
- FIG. 5 presents a comparison of the nucleotide sequences of the Pben509 (nucleotides c994-c1502 of SEQ ID NO:1) and Pben278 (nucleotides g1228-c1502 of SEQ ID NO:1) benzoate -inducible promoters.
- the TTA translational stop site of the upstream ORF, and the putative ⁇ 35 region (TTGACG, nucleotides 1275 through 1280 of SEQ: ID NO:1), ⁇ 10 region (TACGGT, nucleotides 1296 through 1301 of SEQ ID NO:1), and “C” transcription start site are underlined.
- the “C” double-underlined in the Pben278 sequence indicates a mutation in Pben278, which differs from Pben509 and the genomic sequence; this mutation was introduced during PCR amplification.
- FIG. 6 presents a bar chart showing ⁇ -galactosidase induction under the control of Pben509 (pDOW1019) or Pben278 (pDOW1028), in the presence of 0 mm ( ⁇ ) or 10 nM ( ⁇ ) sodium benzoate.
- pDOW1017 is a vector with no promoter. Results shown are average measurements from triplicate wells assayed at 24 hours post-induction (host cells were grown in a defined salts medium for 24 hours prior to induction).
- FIG. 7 presents a comparison of the nucleotide sequences of four Pant promoters: Pant+AntR (a1-cl395 of SEQ ID NO:13), Pant713 (nucleotides c592-c1304 of SEQ ID NO:7), Pant705 (nucleotides c592-g1288 of SEQ ID NO:7), and Pant311 (nucleotides c994-c1304 of SEQ ID NO:7).
- the double-underlined nucleotide triplets (TCA and CAT)respectively indicate the stop and start codons of the AntR ORF, which is encoded by the strand complementary to that shown.
- the lone double-underlined “A” indicates a mutation from the genomic sequence, confirmed on both strands, which lies within the AntR coding sequence; this change results in an expressed change from alanine to serine in the AntR protein.
- the putative ⁇ 35 region (ATAGCC, nucleotides 1238 through 1243 of SEQ ID NO:7), ⁇ 10 region (CTTAAT, nucleotides 1263 through 1267 of SEQ ID NO:7), and transcription start site (“A”), and the complement of the putative ribosome binding site (GGAGG, nucleotides 1817 through 1821 of SEQ ID NO:7) are all underlined.
- FIG. 8 presents a graph comparing the activity of a Pant713 construct (pDOW1029) versus an antR/Pant construct (pDOW1035), when induced with either 5 mM anthranilate or 2 mM 6-chloroanthranilate.
- the promoter was fused to a ⁇ -galactosidase-encoding sequence.
- the activity of the ⁇ -galactosidase reporter was followed over an 8 hour time course post-induction.
- the results show the activity of pDOW1035 following induction occurs much faster and is much higher than that of pDOW1029.
- FIG. 9 presents bar charts showing induction of a Pant-Pben tandem promoter construct, and induction of component promoter constructs. In all constructs, the promoter was fused to a ⁇ -galactosidase-encoding sequence. Induction of a Pant-Pben tandem promoter construct (pDOW1057) with either benzoate or anthranilate is presented in comparison to that of constructs containing one of the component promoters: a Pben promoter construct (pDOW1028), containing Pben278, and a Pant promoter construct (pDOW1035), containing the antR/Pant. FIG. 9A presents results at 5 hours post-induction and FIG. 9B presents results at 24 hours post-induction.
- FIG. 10 presents a bar chart comparison of Pben509 activity to that of improved mutants 2d3 and 21b5, created by error prone PCR of Pben509.
- Expression constructs were formed by fusing promoter-containing fragments to a phoA reporter gene. Cultures containing the constructs were induced with 10 mM benzoate and alkaline phosphatase activity was measured at 24 hours post-induction.
- FIG. 11 presents a comparison of the nucleotide sequences of Pben509 (nucleotides c994-c1502 of SEQ ID NO:1) and two improved mutants thereof created by means of error prone PCR: mutant 2d3 (nucleotides c994-c1502 of SEQ ID NO:1 with a1106 ⁇ t1106) and mutant 21b5 (nucleotides c994-c1502 of SEQ ID NO:1 with c1223 ⁇ t1223 and g1302 ⁇ a1302).
- TTA translational stop site of the upstream ORF and the putative ⁇ 35 region (TTGACG, nucleotides 1275 through 1280 of SEQ ID NO:1), ⁇ 10 region (TACGGT, nucleotides 1296 through 1301 of SEQ ID NO:1), and “C” transcription start site are underlined. Mutations are shown double-underlined.
- FIG. 12 presents a graph of anthranilate-induced expression in 20 L fermentation conditions.
- An antR/Pant construct pDOW1035 ( ⁇ ) and a tandem promoter construct pDOW1057 ( ⁇ ) were induced with 5 mM sodium anthranilate plus a 1 mM/hour anthranilate feed. The activity level for each 20 L fermentation run is shown.
- FIG. 13 presents graphs demonstrating improved anthranilate-induced expression from a tandem promoter construct (pDOW1057) in an antA knockout host created by means of a single crossover knockout of the antA gene in the host cell ( Pseudomonas fluorescens ). Results are shown for 20 L fermentations induced at a target level of about 5 mM sodium anthranilate and followed over a 48 hour time course post-induction. No anthranilate feed was required.
- FIG. 13A presents the activity of ⁇ -galactosidase expressed from the reporter gene construct;
- FIG. 13B shows the maintenance of anthranilate concentration, demonstrating that the knockout host cell does not metabolize anthranilate.
- FIG. 14 presents a bar chart showing induction of Pben ⁇ 10 mutants.
- the alkaline phosphatase activity of P. fluorescens containing the indicated Pben::phoA fusions is shown following 24-hour induction with 0 mM ( ⁇ ) or 5 mM ( ⁇ ) sodium benzoate. Representative experiment of triplicate samples is shown.
- FIG. 15 presents a bar chart showing induction of Pant ⁇ 10 mutants.
- the alkaline phosphatase activity of P. fluorescens antA::kanR containing the indicated Pant::phoA fusions is shown following 24-hour induction with 0 mM (D) or 5 mM ( ⁇ ) anthranilate. Representative experiment of triplicate samples is shown.
- FIG. 16 presents bar charts indicating the effect of Pben88-10 mutations on the activity of the antR-Pant311-Pben tandem promoter.
- the ⁇ -galactosidase activity of P. fluorescens containing the indicated tandem promoter::lacZ fusions is shown following 24-hour induction with 0 mM ( ⁇ ) or 5 mM ( ⁇ ) sodium benzoate ( FIG. 16A ) or anthranilate ( FIG. 16B ). Representative experiment of triplicate samples is shown
- FIG. 17 presents a graph of benzoate consumption during 20 L fermentation when benR is present in multicopy with pDOW1090. Data shown are HPLC analyses measuring the concentration of benzoate throughout the induction of two 20 L fermentors in duplicate fermentations, labeled run “030211I” ( ⁇ ) and run “030211K” ( ⁇ ). The cultures were induced with 5 mM sodium benzoate.
- FIG. 18 presents bar chart comparisons of tandem promoter construct activity.
- the ⁇ -galactosidase activity of P. fluorescens containing the indicated tandem promoter::lacZ fusions (except for pDOW1035, which is ant activator-Pant311::lacZ; and pDOW1126, which is ben activator Pben88 ⁇ 10consensus::lacZ) is shown following induction with 0 or 5 mM sodium benzoate ( FIGS. 18A and 18B for 2, 4, and 24 hour time-points) or anthranilate ( FIGS. 18C and 18D , for 0, 2, 6, and 24 hour time-points). Representative experiment of triplicate samples is shown. Time points are indicated as “post-induction” by the letter “I”.
- FIG. 19 presents a bar chart demonstrating an analysis of Pben activity in the benAB knock-out strain.
- ⁇ -galactosidase activity of a P. fluorescens MB101 benAB knock-out strain carrying pDOW1019 (Pben278::lacZ) is shown as a result of induction with either 0 mM ( ⁇ ) or 5 mM ( ⁇ ) sodium benzoate for up to 24 hours.
- Cells were grown in LB medium.
- the present invention provides commercially useful benzoate-inducible promoters, anthranilate-inducible promoters, and tandem promoters that may be employed in bacterial commercial fermentation systems.
- Preferred bacterial host cells for use in such systems include Pseudomonads and closely related bacteria
- the chemical inducers of these promoters include benzoic and anthranilc acids, their effective chemical analogs, and biologically acceptable salts thereof.
- Benzoic and anthranilic acids and biologically acceptable salts, preferably sodium or potassium salts, thereof, are inexpensive chemicals with low toxicity that can be utilized as (alternative) carbon sources by bacterial host cells, including Pseudomonads and closely related bacteria
- these chemical inducers are available on the market at less than about US$0.15 per gram (versus about US$18 or US$36 per gram for IPTG).
- the present inventors have isolated, sequenced, and characterized the native promoters responsible for expression of the P. fluorescens benzoate (benABCD) degradative genes, which may be induced with benzoate in the absence of glucose, and of the P. fluorescens (antABC) degradative genes, which may be induced with anthranilate.
- benABCD P. fluorescens benzoate
- antiABC P. fluorescens
- the expression products of these operons are catabolic pathway enzymes responsible for degradation of benzoate and anthranilate, respectively, in Pseudomonas fluorescens biotype A.
- These promoters have been found capable of inducing expression of exogenous genes about 250-fold, for the benzoate promoter, and about 25- to about 35-fold, for the anthranilate promoter, when induced with 5 mM sodium benzoate and 5 mM sodium anthranilate, respectively.
- the present inventors have found these promoters to be sufficiently inducible for use in commercial fermentation systems to produce proteins and chemicals in bacterial host cells, including Pseudomonads and closely related bacteria
- tandem promoter constructs in which a non-catabolite-repressed promoter is linked upstream of a natively catabolite-repressed promoter, thereby surprisingly overcoming the catabolite repression of the latter promoter and/or thereby exhibiting a different improved property (e.g., increased strength of induction or increased tightness of regulation).
- a tandem promoter construct has been described for expression of foreign genes [6].
- this example is a tandem arrangement of two copies of the same promoter, Plac, and the reference presents no evidence to suggest that the tandem Plac-Plac promoter has advantages over a single Plac promoter.
- dual promoter constructs are known, e.g., for use in shuttle vectors, in which two promoters operative in different species or genera are both operably attached to the same gene so that the gene can be expressed in either of the two different species or genera.
- tandem promoter constructs in which two non-identical promoters are placed in tandem arrangement, has surprisingly been found to retain advantageous features of both promoters.
- tandem arrangement of the anthranilate promoter, Pant, and the benzoate promoter, Pben has resulted in formation of a tandem promoter that, when induced with anthranilate under fermentation conditions, exhibits both freedom from catabolite repression (a desirable feature of Pant, not shared by Pben) and improved strength of induction (a desirable feature of Pben, not shared by Pant).
- the tandem promoters of the present invention permit retention of desirable properties of the individual promoter elements, so that the resulting tandem promoter can exhibit improved properties: e.g., increased strength of induction, or increased tightness of regulation (i.e. transcription only when contacted with the relevant inducer of the promoter's activator or repressor protein); and/or lack of catabolite repression.
- A450 mean “absorption at a wavelength of 450 nm.”
- a host cell literally defines both those embodiments employing only a single host cell, those employing a plurality of host cells of a single type, and those employing a plurality of host cells of a plurality of types.
- 5-Bromo4-chloro-3-indolyl phosphate e.g., a divalent salt thereof, such as a disodium salt.
- a divalent salt thereof such as a disodium salt.
- tetrazolium salt such as: a halide salt of Nitroblue Tetrazolium (NEBT), e.g., bis-[2-(4-yl-2-methoxyphenyl)3-(4-nitrophenyl)-5-phenyl-tetrazolium chloride]; or of Iodo-Nitro-Tetrazolium (INT), also called Iodoblue Tetrazolium, e.g., 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-phenyl tetrazolium chloride.
- NBT Nitroblue Tetrazolium
- INT Iodo-Nitro-Tetrazolium
- Iodoblue Tetrazolium
- the term “comprising” means that the subject contains the elements enumerated following the term “comprising” as well as any other elements not so enumerated.
- the term “comprising” is to be construed as a broad and open-ended term; thus, a claim to a subject “comprising” enumerated elements is to be construed inclusively, i.e. construed as not limited to the enumerated elements. Therefore, the term “comprising” can be considered synonymous with terms such as, e.g., “having,” “containing,” or “including.”
- corresponding means that a given base sequence contained, as an information string, within the sequence record, is present in the form of a physical nucleobase sequence-containing molecule within the polynucleotide source.
- ddH 2 O refers to distilled, deionized water purified through a Milli-Q gradient system with Q-GARD purification pack (Miripore, Bedford, Mass.).
- dNTPs means an equimolar solution of each of the four deoxyribonucleotide triphosphates (dGTP, dCTP, dATP, dTTP).
- dGTP, dCTP, dATP, dTTP deoxyribonucleotide triphosphates
- 10 mM dNTPs indicates a solution containing 10 mM each of dGTP, dCTP, dATP, and dTTP.
- exogenous means “from a source external to” a given cell or molecule.
- this term is used interchangeably with the term “foreign,” as synonyms. Both of these terms are used herein to indicate that a given object is foreign a given the cell or molecule (e.g., a promoter polynucleotide), i.e. not found in nature in the cell and/or not found in nature with or connected to the molecule.
- heterologous mean “non-identical” in sequence (not 100% identical in base sequence).
- the organisms may be said to be grown “in” or “on” the medium.
- the medium is preferably a gel or liquid medium, more preferably an aqueous gel or liquid medium, and still more preferably an aqueous liquid medium.
- the terms “in” and “on” are used synonymously with one another to indicate growth of the host cells in contact with the medium.
- information string means a series of data elements (e.g., bits, bytes, or alphanumeric characters), which series represents the information of a given series of nucleobases.
- O-Nitrophenyl- ⁇ -D-galactopyranoside also known as 2-Nitrophenyl- ⁇ -D-galactopyranoside.
- para-Nitrophenyl phosphate e.g., a divalent salt thereof, such as a disodium salt.
- a divalent salt thereof such as a disodium salt.
- 4-nitrophenyl phosphate also referred to as 4-nitrophenyl phosphate.
- nucleotides is used to describe the length of polynucleotides. However, in this context, the terminology is meant to refer both to length in nucleotides per se in regard to single stranded polynucleotides, and to length in base pairs in regard to double stranded polynucleotides.
- polynucleotide source means any source of a physical embodiment of a nucleic acid containing a given nucleobase sequence, such as a nucleic acid sample, clone, or native cell containing such a polynucleotide molecule.
- the native activator of a given promoter is designated with an “R” as, e.g., BenR, AntR for the native activators of the Pben and Pant promoters, respectively.
- Pant Promoter for the anthranilate operon of P. fluorescens.
- Pben Promoter for the benzoate operon of P. fluorescens.
- Pant-Pben tandem promoter a tandem arrangement of promoters in which a non-catabolite-repressed promoter is attached to and upstream of, by means of a sequence of 0 to about 100 nucleotides, a catabolite-repressed promoter. This is exemplified herein by Pant-Pben tandem promoter constructs.
- “Promoter” a polynucleotide comprising at least 25 nucleotides, more commonly about 30 nucleotides, containing a prokaryotic “ ⁇ 35 region through ⁇ 10 region.”
- this “ ⁇ 35 region through ⁇ 10 region” is a “ ⁇ 35 region through ⁇ 10 region” obtained from a single gene, or a combination of a ⁇ 35 region and a ⁇ 10 region obtained from cognate genes, the gene(s) being obtained from at least one prokaryote, more preferably at least one organism of the “Pseudomonads and closely related species.”
- the “ ⁇ 35 region through ⁇ 10 region” is a ⁇ 70 “ ⁇ 35 region through ⁇ 10 region,” and the “ ⁇ 35 region” and the “ ⁇ 10 region” in the combination are, respectively, a ⁇ 70 ⁇ 35 region and a ⁇ 70 ⁇ 10 region.
- the ⁇ 35 region is linked upstream of the ⁇ 10 region by an intra-promoter polynucleotide of preferably about 15 to about 20 nucleotides. More preferably, a promoter according to the present invention comprises about 35 nucleotides, which contains, in addition to the “ ⁇ 35 region through ⁇ 10 region,” a segment of about 5 to about 10 immediate downstream nucleotides, more preferably 6 to 7 immediate downstream nucleotides, terminating in a transcription start site nucleotide. In a preferred embodiment, this segment is obtained from the same gene as provides at least one of the ⁇ 35 or ⁇ 10 region.
- the promoter will also contain an immediate upstream region of about 20 to about 250, more preferably about 40 to about 150, nucleotides comprising a promoter activator protein binding site, preferably an AraC/XylS-class binding site.
- the binding site region is obtained from the same gene as provides at least one of the ⁇ 35 or ⁇ 10 region.
- ⁇ 35 region indicates a 5-6 nucleotide sequence beginning approximately 35 nucleotides upstream (i.e. in a 5′ direction from) a transcription start site, the transcription start site being numbered as “+1.”
- ⁇ 10 region or “minus 10” region” indicates a 5-6 nucleotide sequence beginning approximately 10 nucleotides upstream (i.e. in a 5′ direction from) a transcription start site, the transcription start site being numbered as “+1.”
- RNA terms have the definitions recited below.
- search means performing (by manual, visual, or automated means) one or more comparisons between a known information string and other information strings in order to identify an identical or non-identical information string.
- sequence record means a stored embodiment of one or more information strings, such as a computer readable record or a paper record.
- the ⁇ symbol (the times symbol), as used herein in regard to the concentration of a solution, means, e.g., that a 5 ⁇ preparation is five times as concentrated as a 1 ⁇ preparation, for the same solution composition (ie. for the same relative amounts of all components therein).
- Tris as used herein means Tris (hydroxymethyl) aminomethane (available from Fisher Scientific, Pittsburgh, Pa.).
- the promoters of the present invention include the benzoate promoter from Pseudomonas fluorescens , the anthranilate promoter from Pseudomonas fluorescens , and their derivatives.
- the promoters of the present invention also include tandem promoters having a non-catabolite-repressed promoter linked upstream of a natively catabolite-repressed promoter, in which the catabolite repression of the latter promoter is overcome and/or a different improved promoter property is exhibited.
- the promoters of the present invention are typically in the form of DNA when in use in an expression system.
- the nucleobase sequence of the promoters may be present in the form of DNA, RNA, or any nucleic acid analog known in the art, e.g., peptide nucleic acid (PNA).
- PNA peptide nucleic acid
- a benzoate promoter of the present invention is the Pseudomonas fluorescens native benzoate promoter or an improved mutant thereof.
- the present inventors have found this promoter to be inducible with benzoic acid, benzoic acid analogs (e.g., m-toluic acid), and biologically acceptable salts thereof (e.g., sodium benzoate).
- a benzoate promoter of the present invention comprises the ⁇ 35 region of the Pseudomonas fluorescens native benzoate promoter attached upstream of the ⁇ 10 region of this native promoter, via a 15-20 nucleotide linker.
- the linker is 15 nucleotides long.
- a benzoate promoter of the present invention comprises nucleotides 1275-1280 of SEQ ID NO:1 attached upstream of nucleotides 1296-1301 of SEQ ID NO:1, via a 15-20 nucleotide linker.
- the linker is 15 nucleotides long.
- the linker is nucleotides 1281-1295 of SEQ ID NO:1, a benzoate promoter of this preferred embodiment thereby comprising nucleotides 1275-1301 of SEQ ID NO:1.
- a benzoate promoter of the present invention comprises nucleotides 1275-1301 of SEQ ID NO:1 attached immediately upstream of a spacer segment of about 6 nucleotides, preferably of 6 nucleotides, in length, and terminating with a nucleotide that functions as a transcription start site.
- the spacer segment is nucleotides 1302-1307 of SEQ ID NO:1, a benzoate promoter of this preferred embodiment thereby comprising nucleotides 1275-1307 of SEQ ID NO:1.
- a benzoate promoter of the present invention comprises both a “ ⁇ 35 to ⁇ 10 region” and a benzoate promoter activator (or repressor) protein binding site, preferably an activator protein binding site.
- a benzoate promoter of the present invention comprises nucleotides 1275-1301 of SEQ ID NO:1 attached immediately downstream of a spacer region of about 50 nucleotides in length.
- a benzoate promoter of the present invention comprises nucleotides 1275-1301 of SEQ ID NO:1 attached immediately downstream of a spacer region of about 45 nucleotides in length.
- the spacer region has the sequence of the region shown in SEQ ID NO:1, beginning about 50 nucleotides upstream of nucleotide 1275 and ending with nucleotide 1274. In a preferred embodiment, the spacer region has the sequence of the region shown in SEQ ID NO:1, beginning about 45 nucleotides upstream of nucleotide 1275 and ending with nucleotide 1274. In a preferred embodiment, the spacer region has the sequence of nucleotides 1228-1274 of SEQ ID NO:1, a benzoate pronmoter of this preferred embodiment thereby comprising the sequence of nucleotides 1228-1301.
- a benzoate promoter of the present invention comprises nucleotides 1275-1301 of SEQ ID NO:1 attached immediately upstream of said spacer segment and attached immediately downstream of said spacer region. In a preferred embodiment, a benzoate promoter of the present invention comprises nucleotides 1228-1307 of SEQ ID NO:1.
- the host cell in expression systems in which a benzoate promoter according to the present invention is used, will also contain and express at least one nucleic acid encoding a benzoate promoter activator protein. Even more preferred is the use therein of multiple expressed copies of such a Pben activator protein-encoding nucleic acid.
- the Pben activator protein will have an amino acid sequence of SEQ ID NO:2 or the residue 152 (Asn) variant thereof, or an amino acid sequence of residues 21-335 of SEQ ID NO:2 or the residue 152 (Asn) variant thereof.
- the nucleic acid encoding the Pben activator protein will contain the sequence of bases 285-1229 of SEQ ID NO:1 or the base 679 mutant variant thereof, or the sequence of bases 225-1229 of SEQ ID NO:1 or the base 679 mutant variant thereof; or the complement thereof of any of these; or the RNA equivalent of any of these.
- an anthranilate promoter of the present invention is the Pseudomonas fluorescens native anthranilate promoter or an improved mutant thereof.
- the present inventors have found this promoter to be inducible with anthranilic acid, anthranilic acid analogs (e.g., haloanthranilic acids), and biologically acceptable salts thereof (e.g., sodium anthranilate); and with o-toluate (o-toluate has been found to induce this promoter as well as does anthranilate).
- an anthranilate promoter of the present invention comprises the ⁇ 35 region of the Pseudomonas fluorescens native anthranilate promoter attached upstream of the ⁇ 10 region of this native promoter, via a 15-20 nucleotide linker, more preferably a 16-19 nucleotide linker. In a preferred embodiment, the linker is 19 nucleotides long.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1244 of SEQ ID NO:7 attached upstream of nucleotides 1264-1268 of SEQ ID NO:7, via a 15-20 nucleotide linker.
- the linker is 19 nucleotides long.
- the linker is nucleotides 1245-1263 of SEQ ID NO:7, an anthranilate promoter of this preferred embodiment thereby comprising nucleotides 1239-1268 of SEQ ID NO:7.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately upstream of a spacer segment of about 6 nucleotides, preferably of 6 nucleotides, in length, and terminating with a nucleotide that functions as a transcription start site.
- the spacer segment is nucleotides 1269-1274 of SEQ ID NO:7, an anthranilate promoter of this preferred embodiment thereby comprising nucleotides 1239-1274 of SEQ ID NO:7.
- an anthranilate promoter of the present invention comprises both a “ ⁇ 35 to ⁇ 10 region” and an anthranilate promoter activator (or repressor) protein binding site, preferably an activator protein binding site.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 250 nucleotides in length.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 200 nucleotides in length.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 150 nucleotides in length. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 120 nucleotides in length. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 110 nucleotides in length.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 100 nucleotides in length. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 85 nucleotides in length. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 80 nucleotides in length.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 75 nucleotides in length. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 70 nucleotides in length. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 65 nucleotides in length.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 60 nucleotides in length. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 55 nucleotides in length. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1239-1268 of SEQ ID NO:7 attached immediately downstream of a spacer region of about 50 nucleotides in length.
- the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 100 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238. In a preferred embodiment, the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 85 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238. In a preferred embodiment, the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 80 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238.
- the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 75 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238. In a preferred embodiment, the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 70 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238. In a preferred embodiment, the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 65 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238.
- the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 60 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238. In a preferred embodiment, the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 55 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238. In a preferred embodiment, the spacer region has the sequence of the region shown in SEQ ID NO:7, beginning about 50 nucleotides upstream of nucleotide 1239 and ending with nucleotide 1238. In a preferred embodiment, the spacer region has the sequence of nucleotides 1139-1238 of SEQ ID NO:7, an anthranilate promoter of this preferred embodiment comprising nucleotides 1139-1238 of SEQ ID NO:7.
- an anthranilate promoter of the present invention comprises nucleotides 1239-1274 of SEQ ID NO:7 attached immediately upstream of said spacer segment and attached immediately downstream of said spacer region. In a preferred embodiment, an anthranilate promoter of the present invention comprises nucleotides 1139-1274 of SEQ ID NO:7.
- the host cell in expression systems in which an anthranilate promoter according to the present invention is used, will also contain and express at least one nucleic acid encoding an anthranilate promoter activator protein. Even more preferred is the use of multiple expressed copies of such a Pant activator protein-encoding nucleic acid.
- the Pant activator protein will have an amino acid sequence of SEQ ID NO:9 or the residue 268 (Ala) variant thereof.
- the nucleic acid encoding the Pant activator protein will contain the sequence of bases 1-990 of SEQ ID NO:8 or the base 802 variation thereof; or the complement thereof of any of these; or the RNA equivalent of any of these.
- Mutant and Closely Related Activator Proteins and Polynucleotides Encoding Them The same methods as described below for use in obtaining mutant promoters may similarly be used to obtain mutant activator proteins and the coding sequences and genes thereof
- at least a portion of the gene encoding a given activator protein e.g., all or part of the coding sequence thereof, may be used as, or be used to form a probe for use in hybridization probing; or may provide a base sequence to be used in the form of an information string, identical or at least 90% identical thereto, to search a database for structurally related sequences for testing.
- all or part of the amino acid sequence of the activator protein may be used as an information string to perform such searching.
- the resulting sequences identified by hybridization or bioinformatic searching are then tested for promoter activation activity and/or for improved properties.
- transcriptional activator proteins having an amino acid sequence at least 90% identical to and heterologous to that of: a Pben activator protein having an amino acid sequence of any one of residues 1-335 of SEQ ID NO:2, residues 1-335 of SEQ ID NO:2 containing Asn152, residues 21-335 of SEQ ID NO:2, and residues 21-335 of SEQ ID NO:7 containing Asn152; and a Pant activator protein having an amino acid sequence of any one of residues 1-330 of SEQ ID NO:9 and residues 1-330 of SEQ ID NO:9 containing Ala268.
- the present invention also includes polynucleotides encoding said mutant and closely related transcriptional activator proteins.
- a tandem promoter of the present invention comprises a (natively) non-catabolite-repressed promoter attached upstream of a natively catabolite-repressed promoter, in which the catabolite repression of the latter promoter is overcome and/or a different improved promoter property is exhibited.
- both the non-catabolite-repressed promoter and the natively catabolite-repressed promoter are selected from the prokaryotes. In a preferred embodiment, both the non-catabolite-repressed promoter and the natively catabolite-repressed promoter are selected from the bacteria. In a preferred embodiment, both the non-catabolite-repressed promoter and the natively catabolite-repressed promoter are selected from the Proteobacteria; preferably Gram negative Proteobacteria. In a preferred embodiment, both the non-catabolite-repressed promoter and the natively catabolite-repressed promoter are selected from the “Pseudomonads and closely related bacteria” or from a Subgroup thereof, as defined below.
- both promoters are selected from the same species. In a preferred embodiment, both promoters are obtained from the same species in a genus selected from among the “Pseudomonads and closely related bacteria” or among a Subgroup thereof, as defined below. In a preferred embodiment, both promoters are selected from organisms of the genus Pseudomonas . In a preferred embodiment, both promoters are selected from the same species in the genus Pseudomonas . In a preferred embodiment, both promoters are selected from Pseudomonas fluorescens . In a preferred embodiment, both promoters are selected from Pseudomonas fluorescens biotype A.
- the individual promoters selected for use in a tandem promoter according to the present invention may be activatable promoters, repressible promoters, or a combination thereof. In a preferred embodiment at least one of, and preferably both of, the individual promoters will be activatable promoters.
- a repressible promoter is present as a promoter element in such a tandem promoter, preferably the cell in which the tandem promoter is utilized will also contain at least one, and preferably more than, one copy of an expressible coding sequence for a repressor protein that mediates the regulation of the promoter.
- the cell in which the tandem promoter is utilized will also contain at least one, and preferably more than, one copy of an expressible coding sequence for an activator protein that mediates the regulation of the promoter.
- both promoters are obtained as native promoters of genes or operons encoding enzyme(s) and/or pathway(s) capable of enabling a cell to utilize (e.g., to import, export, transport, or metabolize) alternative carbon source(s).
- the non-catabolite-repressed promoter is a native promoter of a gene or operon encoding enzyme(s) and/or pathway(s) capable of biocatalytically degrading anthranilate, i.e.
- the natively catabolite-repressed promoter is a native promoter of a gene or operon encoding enzyme(s) and/or pathway(s) capable of biocatalytically degrading benzoate, i.e. a “benzoate promoter.”
- the anthranilate promoter is an anthranilate promoter as described above.
- the benzoate promoter is a benzoate promoter as described above.
- a tandem promoter of the present invention is a construct formed by linking the Pseudomonas fluorescens native anthranilate promoter to, and upstream of, the Pseudomonas fluorescens native benzoate promoter.
- the present inventors have found such a promoter arrangement to be inducible with anthranilic acid, anthranilic acid analogs (e.g., haloanthranilic acids), and biologically acceptable salts thereof (e.g., sodium anthranilate); with benzoic acid and biologically acceptable salts thereof; and with o-toluate (o-toluate has been found to induce this promoter as well as does anthranilate).
- the non-catabolite-repressed promoter is attached immediately upstream of the natively catabolite-repressed promoter. This attachment may be made directly between the promoters (or directly between native nucleic acid segments containing the promoters) or by means of an, e.g., polynucleotide linker connecting the promoters (or segments) to one another.
- the non-catabolite-repressed promoter is attached upstream of the natively catabolite-repressed promoter, via an inter-promoter linker.
- the inter-promoter linker will be a polynucleotide, provided that that polynucleotide linker contains no sequence that functions as a transcription termination signal.
- the inter-promoter linker is a polynucleotide of about 100 nucleotides in length. In a preferred embodiment, the inter-promoter linker is less than 100 nucleotides in length. In a preferred embodiment the inter-promoter linker is a polynucleotide of length equal to or less than 90 nucleotides. In a preferred embodiment the inter-promoter linker is a polynucleotide of length equal to or less than 80 nucleotides. In a preferred embodiment the inter-promoter linker is a polynucleotide of length equal to or less than 70 nucleotides.
- the inter-promoter linker is a polynucleotide of length equal to or less than 60 nucleotides. In a preferred embodiment the inter-promoter linker is a polynucleotide of length equal to or less than 50 nucleotides. In a preferred embodiment the inter-promoter linker is a polynucleotide of length equal to or less than 40 nucleotides. In a preferred embodiment the inter-promoter linker is a polynucleotide of length equal to or less than 30 nucleotides. In a preferred embodiment the inter-promoter linker is a polynucleotide of length equal to or less than 20 nucleotides.
- the inter-promoter linker is equal to or less than 10 nucleotides.
- the inter-promoter linker is a polynucleotide at least about 5 nucleotides, or at least about 10 nucleotides, or at least about 20 nucleotides, or at least about 30 nucleotides, or at least about 40 nucleotides in length.
- the inter-promoter linker is a polynucleotide about 5 to about 50 nucleotides, or about 10 to about 50 nucleotides, or about 20 to about 50 nucleotides, or about 30 to about 50 nucleotides in length.
- the inter-promoter linker is a polynucleotide having a length of 43 nucleotides.
- the inter-promoter linker has the sequence of SEQ ID NO:14.
- a tandem promoter comprises an anthranilate promoter sequence selected from the group consisting of nucleotides 1221-1365, 1221-1371, 1329-1365, and 1329-1371 of SEQ ID NO:13 attached upstream of a benzoate promoter sequence selected from the group consisting of nucleotides 1430-1503, 1430-1509, 1477-1503, and 1477-1509 of SEQ ID NO:13.
- a tandem anthranilate-benzoate promoter of the present invention comprises, for the benzoate promoter portion, both a “ ⁇ 35 to ⁇ 10 region” and a benzoate promoter activator (or repressor) protein binding site, preferably an activator protein binding site.
- a tandem promoter comprises nucleotides 1329-1503 of SEQ ID NO:13. In a preferred embodiment, a tandem promoter comprises nucleotides 1329-1509 of SEQ ID NO:13. In a preferred embodiment, a tandem promoter comprises nucleotides 1221-1503 of SEQ ID NO:13. In a preferred embodiment, a tandem promoter comprises nucleotides 1221-1503 of SEQ ID NO:13. In a preferred embodiment, a tandem promoter comprises nucleotides 1221-1509 of SEQ ID NO:13. In a preferred embodiment, a tandem promoter comprises nucleotides 1329-1544 of SEQ ID NO:13. In a preferred embodiment, a tandem promoter comprises nucleotides 1221-1544 of SEQ ID NO:13.
- an anthranilate activator protein coding sequence or a benzoate activator protein coding sequence is included in, and expressed within, a system using, respectively, a Pant-containing or Pben-containing tandem promoter of the present invention
- a Pant-containing or Pben-containing tandem promoter of the present invention where the tandem promoter contains both a Pant and a Pben, preferably an anthranilate promoter activator protein coding sequence is selected, for example, the anthranilate activator protein (AntR) described above in regard to Pant promoters.
- Anthranilate activator protein AntR
- Even more preferred in any expression system is the presence of such an expressed coding sequence in multiple copies.
- Tandem promoters may be constructed, e.g., by obtaining from prokaryotic cells, preferably bacterial cells, native promoters from genes or operons encoding enzyme(s) responsible for utilization of alternative carbon sources, i.e. carbon sources other than glucose.
- the bacterial cells will be chosen from among the bacterial cells belonging to the “Pseudomonads and closely related bacteria,” or any one of the 19 Subgroups thereof, as defined below.
- a native promoter selected for use in constructing a tandem promoter will be obtained from a gene or operon from which is expressed an enzyme(s) having degradative activity toward at least one alternative carbon source chosen from among:
- the genes and operons encoding these biodegradative activities may be either catabolite-repressed or non-catabolite-repressed, as described above.
- the native promoters thereof may be readily obtained by one of ordinary skill in the art by methods well known in the art, e.g., by isolating mRNA encoding such an enzyme and using the nucleic acid sequence of the mRNA or cDNA made therefrom, to probe the bacterial genome (or a record of the genomic sequence thereof) for occurrence(s) of the corresponding DNA gene. This is followed by identification of regulatory regions, including a transcription start site, located in the segment of DNA immediately upstream of (i.e. 5′ to) the coding sequence.
- Expression constructs containing such regulatory region nucleic acid sequences are then formed and the expression construct(s) tested for induction in bacterial host cells by one or more alternative carbon source compounds, both in the presence and absence of glucose.
- This provides catabolite-repressed and non-catabolite-repressed promoters that may be used in constructing a tandem promoter according to the present invention.
- catabolite repressed and non-catabolite-repressed genes and operons are known that either (a) encode enzymes that utilize (e.g., that transport, anabolize, or catabolize) alternative carbon sources or (b) encode regulatory genes that control expression from such enzyme-encoding gene(s) and operon(s).
- the promoter of a typical gene or operon of this type is regulated in that transcription therefrom depends upon, le. the promoter is induced or derepressed by, the presence of a relevant alternative carbon source or an analog compound thereof.
- catabolite repressed genes and operons examples include, e.g.:
- non-catabolite-repressed genes and operons examples include, e.g.:
- Mutant promoters made from a promoter(s) of a preferred embodiment hereof may also be created using any of the various random and/or directed, mutagenesis techniques known in the art.
- site-specific mutagenesis will be performed (e.g. via mutagenic oligonucleotide-directed mutagenesis).
- an improved mutant promoter will be selected from a library of mutants made by an error-prone polymerase chain reaction (EP-PCR) performed on a promoter polynucleotide. Multiple rounds of mutagenesis may be performed either upon the pool of polynucleotides resulting from a previous round or upon one or more mutant promoters selected therefrom.
- Advantageous mutations identified in improved promoters may also be combined to obtain further increases in improvement (e.g., cumulative improvements).
- mutant tandem promoters In addition to generating mutant tandem promoters by performing one or more of the techniques described above upon a non-mutant tandem promoter (i.e. a tandem promoter in which the individual promoter elements are themselves of native sequence), individual mutant promoters may be used in forming a tandem promoter(s) according to the present invention. For example, two mutant promoters may be linked together, or a mutant promoter and a non-mutant promoter may be linked together, to form a tandem promoter according to the present invention.
- directed mutagenesis and/or recombination may be performed (e.g., using a technique such as is described in WO 91/16427) in order to create multiple promoter-promoter combinations in a given round.
- promoters may be obtained by use of polynucleotides containing tandem and/or native promoter constructs and/or elements as hybridization probes, under stringent hybridization conditions, according to any of the various protocols known in the art.
- An exemplary stringent hybridization protocol is set forth below.
- a peptide nucleic acid (PNA), or other nucleic acid analog, having a base sequence of such a promoter may be used as a hybridization probe.
- the probe will contain a base sequence of at least about 6, at least about 8, at least about 10, at least about 15, at least about 20, at least about 25, at least about 30, at least about 35, at least about 40, at least about 45, or at least about 50 bases in length.
- the probe will contain a base sequence of not more than about 100, about 80, about 60, or about 50 bases in length. In a preferred embodiment, the probe will contain a base sequence of about 20 to about 50, or about 25 to about 45, or about 30 to about 40 bases in length.
- target nucleic acids e.g., target DNA at least suspected of containing a promoter
- the target DNA to be probed is denatured, blotted crosslinked onto a nitrocellulose or nylon membrane according to standard protocols (see Sambrook et al. [Cold Spring Harbor Press], Current Protocols in Molecular Biology [John Wiley and Sons, Inc.]).
- the blot is then pre-hybridized using standard buffers as described in Sambrook et al. or Current Protocols or using a commercially available hybridization buffer such as EXPRESSHYB (BD Biosciences Clontech, Palo Alto, Calif.). Pre-hybridization may be performed at temperatures ranging from 50-65° C.
- the probe to be used may be labeled to identify specifically bound target DNA and/or the probe nucleic acid may be used as a primer to enzymatically copy specifically bound target DNA.
- the probe may be labeled according to any of the techniques known in the art.
- the probe may be labeled with any detectable label, including, but not limited to a: peptide tag, an immunogenic moiety, avidin, biotin, a fluorescent or colored moiety, a detectable chelate, or a radionuclide moiety.
- a nucleic acid preferably DNA, is used as the probe.
- the DNA of the probe is labeled.
- the label is a radioactive moiety, e.g., a radionuclide-containing compound such as ⁇ - 32 P dATP.
- Kits for performing such labeling are commercially available: for example, the HIGH PRIME DNA labeling kit (Roche Molecular Biochemicals, Indianapolis, Ind.), in conjunction with a radionuclide-containing nucleoside-5′-triphosphate, such as ⁇ - 32 P dATP, may be used.
- the probe or labeled probe is then boiled and added to the pre-hybridization buffer. The blot is incubated with the probe at 50-65° C.
- the blot is then developed as appropriate for viewing the specifically bound labeled probe. For example, if a radionuclide moiety is used as the label on the probe, the blot is used to expose a film or a phosphor screen for viewing.
- an oligo or set of oligos may be designed that hybridize to known promoter elements (i.e., the ⁇ 35 and ⁇ 10 sequences with intervening sequence), or to known activator protein binding sites; a set of degenerate oligos can be designed, at least one of which can hybridize to the target sequence of interest. These may be used as probes for Southern blot analysis as described above, or may be used to initiate synthesis of single (one oligo) or double (two oligos) stranded DNA that may be homologous to the promoter of interest. DNA synthesis may be carried out with, e.g., Taq polymerase (with extension carried out at 72° C.
- a selected target nucleic acid will be at least 90% homologous, i.e. at least 90% identical in base sequence to the probe or the complementary base sequence thereof (wherein T and U are considered equivalent bases for these purposes).
- a selected target nucleic acid will be at least about 95% homologous thereto.
- a selected target nucleic acid will be at least about 98% homologous thereto.
- target nucleic acid is situated as a portion within a larger polynucleotide molecule
- the target nucleic acid, or a fragment containing said target nucleic acid may be recovered therefrom by any means known in the art, including, e.g., endonuclease digestion and exonuclease digestion.
- the base sequence of the probe may be used, in the form of an information string, to perform searching of a nucleotide sequence record, such as a paper or electronic database record of nucleotide sequences present in polynucleotides containing with a polynucleotide source.
- the search parameters may specify that a successful match must be 100% identical (100% homologous) or less than 100% identical (heterologous) to the probe information string.
- the search parameters will be selected so that a successful match must be at least 90% homologous, at least 95% homologous, or at least 98% homologous to the probe information string.
- the search parameters will be selected so that a successful match must be heterologous to the probe information string.
- a probe information string may be created by altering a first information string representing the nucleobase sequence of a given promoter from a modified information string representing a heterologous nucleobase sequence at least 90% homologous to that of said given promoter.
- This modified information string may then be used to synthesize a polynucleotide molecule containing the base sequence thereof or may be used to perform searching of a nucleotide sequence record for an identical information string as described above.
- the polynucleotide source corresponding thereto is selected.
- a polynucleotide at least 90% homologous to the probe sequence is obtained, it is then tested, by forming an expression construct therewith, inserting the expression construct into a transcription system (or transcription and translation system), such as a prokaryotic host cell, and screening the resulting system, e.g., the transformed cell, for the ability of the polynucleotide to direct transcription.
- a transcription system or transcription and translation system
- the screening also involves identifying at least one promoter property improved relative to that of the original promoter.
- Alignments and searches for homologous sequences can be performed using the U.S. National Center for Biotechnology Information (NCBI) program, MegaBLAST (currently available at http://www.ncbi.nlm.nih.gov/BLAST/). Use of this program with options for percent identity set at 90% will identify those sequences with 90% or greater homology to the query sequence.
- Other software known in the art is also available for aligning and/or searching for homologous sequences, e.g., sequences at least 90% homologous to an information string containing a promoter base sequence or activator-protein-encoding base sequence according to the present invention.
- sequence alignments for comparison to identify sequences at least 90% homologous to a query sequence can be performed by use of, e.g., the GAP, BESTFIT, BLAST, FASTA, and TFASTA programs available in the GCG Sequence Analysis Software Package (available from the Genetics Computer Group, University of Wisconsin Biotechnology Center, 1710 University Avenue, Madison, Wis. 53705), with the default parameters as specified therein, plus a parameter for the extent of homology set at 90%.
- the CLUSTAL program available in the PC/Gene software package from Intelligenetics, Mountain View, Calif. may be used.
- sequence alignment methods are well known in the art and may be conducted by manual alignment, by visual inspection, or by manual or automatic application of a sequence alignment algorithm, such as any of those embodied by the above-described programs.
- Various useful algorithms include, e.g.: the similarity search method described in W. R. Pearson & D. J. Lipman, Proc. Nat'l Acad. Sci. USA 85:244448 (April 1988); the local homology method described in T. F. Smith & M. S. Waterman, in Adv. Appl. Math. 2:482-89 (1981) and in J. Molec. Biol. 147:195-97 (1981); the homology alignment method described in S. B. Needleman & C. D. Wunsch, J.
- a nucleobase polymer e.g., a polynucleotide or polynucleotide analog
- a nucleobase polymer that is heterologous to, i.e. whose base sequence is heterologous to, the base sequence of a given promoter, promoter region, or other non-codon- or non-anti-codon-containing polynucleotide segment, will be at least 90% homologous thereto; preferably about or at least 93% homologous thereto; preferably about or at least 95% homologous thereto; preferably about or at least 96% homologous thereto; preferably about or at least 97% homologous thereto; preferably about or at least 98% homologous thereto; preferably about or at least 99% thereto.
- a polypeptide (or segment thereof) that is heterologous to, i.e. whose amino acid sequence is heterologous to, the amino acid sequence of a given polypeptide (or segment thereof) will be at least 90% homologous thereto; preferably about or at least 93% homologous thereto; preferably about or at least 95% homologous thereto; preferably about or at least 96% homologous thereto; preferably about or at least 97% homologous thereto; preferably about or at least 98% homologous thereto; preferably about or at least 99% thereto.
- a nucleobase polymer (or segment thereof) that is heterologous to, i.e. whose base sequence is heterologous to, the base sequence of a given codon- or anti-codon-containing polynucleotide (or segment thereof), will be at least 90% homologous thereto; preferably about or at least 93% homologous thereto; even more preferably about or at least 95% homologous thereto; still more preferably about or at least 96% homologous thereto.
- such a nucleobase polymer has such a degree of homology to the given codon- or anti-codon-containing polynucleotide that the amino acid sequence encoded by the nucleobase polymer will be at least 90% homologous to the amino acid sequence of the given polynucleotide; preferably about or at least 93% homologous thereto; preferably about or at least 95% homologous thereto; preferably about or at least 96% homologous thereto; preferably about or at least 97% homologous thereto; preferably about or at least 98% homologous thereto; preferably about or at least 99% thereto.
- a nucleobase polymer (or segment thereof) that is heterologous to, i.e. whose base sequence is heterologous to, the base sequence of a given codon- or anti-codon-containing polynucleotide (or segment thereof), is about or at least 97% homologous thereto; preferably about or at least 98% homologous thereto; preferably about or at least 99% thereto.
- a nucleic acid containing a transcription product-encoding sequence will be operably linked to a promoter according to the present invention, spacer.
- the transcription product is an mRNA or a precursor molecule thereto
- the spacer will be a ribosome-binding-site-containing spacer (“RBS spacer”).
- a “transcription product-encoding polynucleotide” is any polynucleotide that contains a transcription product-encoding sequence, wherein the transcription product is any functional or structural RNA molecule, including, but not limited to, e.g., mRNA, rRNA, tRNA, cRNA, gRNA, hnRNA, miRNA, mtRNA, nRNA, ncRNA, pRNA, satRNA, scRNA, siRNA, snRNA, snoRNA, srpRNA, stRNA, tmRNA, vRNA, anti-sense RNA (also called “aRNA”), aptamer RNA, chromosomal RNA, enzyme-inhibitor RNA, genetic-control-element RNA, plastid RNA, ribozyme RNA, self-cleaving RNA, self-splicing RNA, telomerase RNA (TER or TERC), X-chromosome-inactiv
- elements may be included in an expression construct. Such elements include, but are not limited to, e.g.: transcriptional enhancer sequences; translational enhancer sequences; leader peptide-encoding sequences, e.g., for intra-cellular-targeting-peptides or secretion signal peptides; pro-peptide-, pre-peptide-, and pre-pro-peptide-coding sequences; other promoters; translational start and stop signals; polyadenylation signals; transcription terminators; introns; and tag sequences, such nucleotide sequence “tags” and “tag” peptide coding sequences (a “tag” facilitates identification, separation, purification, or isolation of an expressed polynucleotide, for which a nucleotide sequence tag is used, or of an expressed polypeptide, for which a “tag” peptide coding sequence is used).
- an expression construct according to the present invention will include (in addition to a promoter and either a spacer or an RBS-spacer, operably linked to a transcription product-encoding sequence), a transcriptional terminator. Where the transcription product is an mRNA or pre-mRNA, the expression construct will, at minimum, further include translational start and stop signals operably linked to the transcription product-encoding sequence.
- the term “operably linked,” as used herein, refers to any configuration in which the transcriptional and any translational regulatory elements are covalently attached to the encoding sequence in such disposition(s), relative to the encoding sequence, that in and by action of the host cell, the regulatory elements can direct the expression of the coding sequence.
- Every regulatory element in the expression construct must be “operably linked” to the transcription product-encoding sequence.
- the regulatory element(s) must be so positioned that the cell's processing systems can manipulate the expression construct or the pre-RNA to operably link the regulatory element(s) therein.
- the segments i.e.
- the polynucleotide molecules or regions collectively containing the regulatory element(s) and transcription product-encoding sequence(s), must be so positioned that the cell can manipulate the segments to create or to re-connect the expression construct wherein the regulatory elements are operatively linked to the transcription product-encoding sequence, and/or are so positioned that the cell's processing systems can manipulate a to-be-transcribed pre-RNA to operably link the regulatory element(s) thereto.
- Any prokaryotic ribosome binding site may be utilized in such an expression construct.
- a bacterial RBS is utilized.
- an RBS operative in Gram positive bacteria is used; even more preferably an RBS operative in Gram negative bacteria is used.
- consensus RBSs are known, e.g., those described in and referenced by D. Frishman et al., Starts of bacterial genes: estimating the reliability of computer predictions, Gene 234(2):257-65 (8 Jul. 1999); and B. E. Suzek et al., A probabilistic method for identifying start codons in bacterial genomes, Bioinformatics 17(12):1123-30 (December 2001).
- RBSs either native or synthetic RBSs may be used, e.g., those described in: EP 0207459 (synthetic RBSs); O. Ikehata et al., Primary structure of nitrile hydratase deduced from the nucleotide sequence of a Rhodococcus species and its expression in Escherichia coli, Eur. J. Biochem. 181(3):563-70 (1989) (native RBS sequence of AAGGAAG, SEQ ID NO:42); or J. A. Wells et al., Cloning, sequencing, and secretion of Bacillus amyloliquefaciens subtilisin in Bacillus subtilis, Nucl. Acids Res. 11(22):7911-25 (1983) (native RBS sequence of GAGAGG, SEQ ID NO:43).
- one or more marker genes or reporter genes may be used in an expression system to verify expression.
- Many such useful marker or reporter genes are known in the art. See, e.g., U.S. Pat. No. 4,753,876 to Hemming et al., and DL Day et al., in J. Bact. 157(3):937-39 (March 1984).
- the marker gene is selected from among the antibiotic resistance-conferring marker genes.
- the marker gene is selected from among the tetracycline and kanamycin resistance genes.
- a reporter gene is selected from among those encoding: (1) fluorescent proteins (e.g., GFP); (2) colored proteins; and (3) fluorescence- or color-facilitating or -inducing proteins, the latter class (3) including, e.g., luminases, alkaline phosphatases, and beta-galactosidases.
- Alkaline phosphatases hydrolyze BCIP to produce a blue color
- PNPP hydrolyze PNPP to produce a yellow color.
- Beta-galactosidases hydrolyze X-gal to create a blue-colored derivative, and hydrolyze ONPG to produce a yellow color.
- Fluorescent substrates are also available for alkaline phosphatase and ⁇ -galactosidase.
- a great many bacterial vectors are known in the art as useful for expressing proteins in bacteria, and any of these may be used for expressing the genes according to the present invention.
- Such vectors include, e.g., plasmids, cosmids, and phage expression vectors.
- useful plasmid vectors include, but are not limited to, the expression plasmids pMB9, pBR312, pBR322, pML122, RK2, RK6, and RSF1010.
- Other examples of such useful vectors include those described by, e.g.: N. Hayase, in Appl. Envir. Microbiol. 60(9):3336-42 (September 1994); A. A. Lushnikov et al, in Basic Life Sci.
- RSF1010 The expression plasmid, RSF1010, is described, e.g., by F. Heffron et al., in Proc. Nat'l Acad. Sci. USA 72(9):3623-27 (September 1975), and by K. Nagahari & K. Sakaguchi, in J. Bact. 133(3):1527-29 (March 1978). Plasmid RSF1010 and derivatives thereof are particularly useful vectors in the present invention.
- Exemplary, useful derivatives of RSF1010 include, e.g., pKT212, pKT214, pKT231 and related plasmids, and pMYC1050 and related plasmids (see, e.g., U.S. Pat. Nos. 5,527,883 and 5,840,554 to Thompson et al.), such a, e.g., pMYC1803.
- Other exemplary useful vectors include those described in U.S. Pat. No. 4,680,264 to Puhler et al.
- an expression plasmid is used as the expression vector.
- RSF1010 or a derivative thereof is used as the expression vector.
- pMYC1050 or a derivative thereof, or pMYC1803 or a derivative thereof is used as the expression vector.
- a vector can then be transformed into a bacterial host cell.
- Transformation of the host cells with the vector(s) may be performed using any transformation methodology known in the art, and the bacterial host cells may be transformed as intact cells or as protoplasts (i.e. including cytoplasts).
- Exemplary transformation methodologies include poration methodologies, e.g., electroporation, protoplast fusion, bacterial conjugation, and divalent cation treatment, e.g., calcium chloride treatment or CaCl/Mg 2+ treatment.
- the bacterial host cell will also contain at least one, and preferably more than one, copy of a gene containing a coding sequence of an activator or repressor protein of the promoter.
- This gene may be attached to the expression construct, or it may be part of a separate nucleic acid.
- an anthranilate activator protein having the amino acid sequence encoded by the complement of the coding sequence shown at nucleotides 4-993 of SEQ ID NO:7 will be utilized; and a benzoate activator protein encoded by nucleotides 225-1229 or nucleotides 285-1229 of SEQ ID NO:1 will be utilized.
- the activator- (or repressor-) encoding gene will be constitutively expressed in the bacterial host cell.
- the host cell will be contacted with an activator (or de-repressor) compound to induce expression.
- the bacterial host cell will be contacted with anthranilic or benzoic acid or a biologically acceptable salt (preferably a sodium salt) thereof, in the case of anthranilate and benzoate promoters, respectively.
- the bacterial host cell will be contacted with an inducer compound that induces either the natively catabolite-repressed promoter element or the (natively) non-catabolite-repressed promoter element thereof.
- an inducer compound that induces either the natively catabolite-repressed promoter element or the (natively) non-catabolite-repressed promoter element thereof.
- benzoic acid, anthranilic acid, or biologically acceptable salt(s) (preferably a sodium salt) thereof will be used as the inducer (activator) compound.
- the host cell in which the promoter is used will be selected from the prokaryotes.
- the host cell is selected from the bacteria.
- the host cell is selected from the Proteobacteria.
- the host cell is selected from the “Pseudomonads and closely related bacteria” or from a Subgroup thereof, as defined below.
- the host cell is selected from the genus Pseudomonas .
- a particularly preferred species of Pseudomonas is P. fluorescens; even more preferred is Pseudomonas fluorescens biotype A.
- both the organism from which the native promoter(s) are obtained and the host cells in which a promoter according to the present invention is utilized will be selected from the prokaryotes. In a preferred embodiment, both the organism from which the native promoter(s) are obtained and the host cells in which a promoter according to the present invention is utilized, will be selected from the bacteria. In a preferred embodiment, both the bacteria from which the native promoter(s) are obtained and the bacterial host cells in which a promoter according to the present invention is utilized, will be selected from the Proteobacteria.
- both the bacteria from which the native promoter(s) are obtained and the bacterial host cells in which a promoter according to the present invention is utilized will be selected from the Pseudomonads and closely related bacteria or from a Subgroup thereof, as defined below.
- both the promoter source organism and the host cell will be selected from the same species.
- the species will be a prokaryote; more preferably a bacterium, still more preferably a Proteobacterium.
- both the promoter source organism and the host cell will be selected from the same species in a genus selected from the Pseudomonads and closely related bacteria or from a Subgroup thereof, as defined below; more preferably from the genus Pseudomonas.
- the species Pseudomonas fluorescens even more preferably, Pseudomonas fluorescens biotype A.
- the host cells in which the promoter is used will lack biocatalyst(s) effective to degrade the inducer compound: e.g., benzoate or anthranilate or an analog thereof, and/or the degradation product(s) thereof, if any, that is directly responsible for induction; and/or gratuitous inducer compounds.
- Such host cells are readily obtained as knock-out mutants.
- the present inventors have found that, in the case of an anthranilate promoter, inactivation of at least the antA portion of the host cell's antABC operon does inhibit the consumption of an anthranilate inducer and thereby permits the inducer to effect lasting induction.
- the antA open reading frame encodes the large subunit of the first enzyme utilized in the pathway for degradation of anthranilate.
- a benzoate promoter the inventors have found that inactivation of the benAB portion of the host cell's benABCD operon, e.g., by deletion or mutation, does inhibit the consumption of a benzoate inducer, thereby improving the level of induction; inactivation of at least the beta portion would work similarly, as this encodes the large subunit of the first enzyme utilized in the pathway for degradation of benzoate.
- Gene knock-outs may be constructed according to any method known effective in the art. Gene inactivation by insertion of a gene has been previously described. See, e.g., D L Roeder & A Collmer, Marker - exchange mutagenesis of a pectate lyase isozyme gene in Erwinia chrysanthemi , J Bacteriol. 164(1):51-56 (1985). Briefly, a portion of the gene to be disrupted in amplified and cloned into a vector containing a selectable marker, such as an antibiotic resistance gene, that is not able to replicate in the target host.
- a selectable marker such as an antibiotic resistance gene
- transposon mutagenesis and selection for desired phenotype may be used to isolate bacterial strains in which target genes have been insertionally inactivated. See, e.g., K Nida & P P Cleary, Insertional inactivation of streptolysin S expression in Streptococcus pyogenes , J Bacteriol. 155(3):1156-61 (1983).
- cassette mutagenesis for example, a described in J A Wells et al., Cassette mutagenesis: an efficient method for generation of multiple mutations at defined sites , Gene 34(2-3):315-23 (1985); whereby direct or random mutations are made in a selected portion of a gene, and then incorporated into the chromosomal copy of the gene by homologous recombination.
- Gram( ⁇ ) Proteobacteria Subgroup 1 is more specifically defined as the group of Proteobacteria belonging to the families and/or genera described as falling within that taxonomic “Part” named “Gram-Negative Aerobic Rods and Cocci” by R. E. Buchanan and N. E. Gibbons (eds.), Bergey's Manual of Determinative Bacteriology , pp.
- “Gram( ⁇ ) Proteobacteria Subgroup 1” contains all Proteobacteria classified thereunder, as well as all Proteobacteria that would be classified thereunder according to the criteria used in forming that taxonomic “Part.” As a result, “Gram( ⁇ ) Proteobacteria Subgroup 1” excludes, e.g.: all Gram-positive bacteria; those Gram-negative bacteria, such as the Enterobacteriaceae, which fall under others of the 19 “Parts” of this Bergey (1974) taxonomy; the entire “Family V.
- Halobacteriaceae of this Bergey (1974) “Part,” which family has since been recognized as being a non-bacterial family of Archaea; and the genus, Thermus , listed within this Bergey (1974) “Part,” which genus which has since been recognized as being a non-Proteobacterial genus of bacteria.
- Gram( ⁇ ) Proteobacteria Subgroup 1 further includes those Proteobacteria belonging to (and previously called species of) the genera and families defined in this Bergey (1974) “Part,” and which have since been given other Proteobacterial taxonomnic names. In some cases, these re-namings resulted in the creation of entirely new Proteobacterial genera.
- the genera Acidovorax, Brevundimonas, Burkholderia, Hydrogenophaga, Oceanimonas, Ralstonia , and Stenotrophomonas were created by regrouping organisms belonging to (and previously called species of) the genus Pseudomonas as defined in Bergey (1974).
- the genus Sphingomonas (and the genus Blastomonas , derived therefrom) was created by regrouping organisms belonging to (and previously called species of) the genus Xanthomonas as defined in Bergey (1974).
- the genus Acidomonas was created by regrouping organisms belonging to (and previously called species of) the genus Acetobacter as defined in Bergey (1974). Such subsequently reassigned species are also included within “Gram( ⁇ ) Proteobacteria Subgroup 1” as defined herein.
- Proteobacterial species falling within the genera and families defined in this Bergey (1974) “Part” were simply reclassified under other, existing genera of Proteobacteria.
- Pseudomonas Pseudomonas enalia (ATCC 14393), Pseudomonas nigrifaciens (ATCC 19375), and Pseudomonas putrefaciens (ATCC 8071) have since been reclassified respectively as Alteromonas haloplanktis, Alteromonas nigrifaciens , and Alteromonas putrefaciens .
- Pseudomonas acidovorans (ATCC 15668) and Pseudomonas testosteroni (ATCC 11996) have since been reclassified as Comamonas acidovorans and Comamonas testosteroni , respectively; and Pseudomonas nigrifaciens (ATCC 19375) and Pseudomonas piscicida (ATCC 15057) have since been reclassified respectively as Pseudoalteromonas nigrifaciens and Pseudoalteromonas piscicida .
- Such subsequently reassigned Proteobacterial species are also included within “Gram( ⁇ ) Proteobacteria Subgroup 1” as defined herein.
- “Gram( ⁇ ) Proteobacteria Subgroup 1I” fiurter includes Proteobacterial species that have since been discovered, or that have since been reclassified as belonging, within the Proteobacterial families and/or genera of this Bergey (1974) “Part.”
- “Gram( ⁇ ) Proteobacteria Subgroup 1” also includes Proteobacteria classified as belonging to any of the families: Pseudomonadaceae, Azotobacteraceae (now often called by the synonym, the “Azotobacter group” of Pseudomonadaceae), Rhizobiaceae, and Methylomonadaceae (now often called by the synonym, “Methylococcaceae”).
- Proteobacterial genera falling within “Gram( ⁇ ) Proteobacteria Subgroup1” include: 1) Azotobacter group bacteria of the genus Azorhizophilus; 2) Pseudomonadaceae family bacteria of the genera Cellvibrio, Oligella , and Teredinibacter; 3) Rhizobiaceae family bacteria of the genera Chelatobacter, Ensifer, Liberibacter (also called “ Candidatus Liberibacter” ), and Sinorhizobium; and 4)Methylococcaceae family bacteria of the genera Methylobacter, Methylocaldum, Methylomicrobium, Methylosarcina, and Methylosphaera.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 1,” as defined above.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 2.”
- “Gram( ⁇ ) Proteobacteria Subgroup 2” is defined as the group of Proteobacteria of the following genera (with the total numbers of catalog-listed, publicly-available, deposited strains thereof indicated in parenthesis, all deposited at ATCC, except as otherwise indicated): Acidomonas (2); Acetobacter (93); Gluconobacter (37); Brevundimonas (23); Beijerinckia (13); Derxia (2); Brucella (4); Agrobacterium (79); Chelatobacter (2); Ensifer (3); Rhizobium (144); Sinorhizobium (24); Blastomonas (1); Sphingomonas (27); Alcaligenes (88); Bordetella (43); Burkholderia (73); Ralstonia (33); Acidovorax (20); Hydrogenophaga (9); Zoogloea (9); Methyl
- Exemplary species of “Gram( ⁇ ) Proteobacteria Subgroup 2” include, but are not limited to the following bacteria (with the ATCC or other deposit numbers of exemplary strain(s) thereof shown in parenthesis): Acidomonas methanolica (ATCC 43581); Acetobacter aceti (ATCC 15973); Gluconobacter oxydans (ATCC 19357); Brevundimonas diminuta (ATCC 11568); Beijerinckia indica (ATCC 9039 and ATCC 19361); Derxia gummosa (ATCC 15994); Brucella melitensis (ATCC 23456), Brucella abortus (ATCC 23448); Agrobacterium tumefaciens (ATCC 23308), Agrobacterium radiobacter (ATCC 19358), Agrobacterium rhizogenes (ATCC 11325); Chelatobacter heintzii (ATCC 29600); Ensifer adhaerens (ATCC
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 3.”
- “Gram( ⁇ ) Proteobacteria Subgroup 3” is defined as the group of Proteobacteria of the following genera: Brevundimonas; Agrobacterium; Rhizobium; Sinorhizobium; Blastomonas; Sphingomonas; Alcaligenes; Burkholderia; Ralstonia; Acidovorax; Hydrogenophaga; Methylobacter; Methylocaldum; Methylococcus; Methylomicrobium; Methylomonas; Methylosarcina; Methylosphaera; Azomonas; Azorhizophilus; Azotobacter; Cellvibrio; Oligella; Pseudomonas; Teredinibacter; Francisella; Stenotrophomonas; Xanthomonas; Oceanimonas; and Acinetobacter
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 4.”
- “Gram( ⁇ ) Proteobacteria Subgroup 4” is defined as the group of Proteobacteria of the following genera: Brevundimonas; Blastomonas; Sphingomonas; Burkholderia; Ralstonia; Acidovorax; Hydrogenophaga; Methylobacter; Methylocaldum; Methylococcus; Methylomicrobium; Methylomonas; Methylosarcina; Methylosphaera; Azomonas; Azorhizophilus; Azotobacter; Cellvibrio; Oligella; Pseudomonas; Teredinibacter; Francisella; Stenotrophomonas; Xanthomonas; Oceanimonas; and Acinetobacter.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 5.”
- “Gram( ⁇ ) Proteobacteria Subgroup 5” is defined as the group of Proteobacteria of the following genera: Methylobacter; Methylocaldum; Methylococcus; Methylomicrobium; Methylomonas; Methylosarcina; Methylosphaera; Azomonas; Azorhizophilus; Azotobacter; Cellvibrio; Oligella; Pseudomonas; Teredinibacter; Francisella; Stenotrophomonas; Xanthomonas; Oceanimonas; and Acinetobacter.
- the host cell is selected from “Gram( ⁇ ) Proteobacteria Subgroup 6.”
- “Gram( ⁇ ) Proteobacteria Subgroup 6” is defined as the group of Proteobacteria of the following genera: Brevundimonas; Blastomonas; Sphingomonas; Burkholderia; Ralstonia; Acidovorax; Hydrogenophaga; Azomonas; Azorhizophilus; Azotobacter; Cellvibrio; Oligella; Pseudomonas; Teredinibacter; Stenotrophomonas; Xanthomonas; Oceanimonas; and Acinetobacter.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 7.”
- “Gram( ⁇ ) Proteobacteria Subgroup 7” is defined as the group of Proteobacteria of the following genera: Azomonas; Azorhizophilus; Azotobacter; Cellvibrio; Oligella; Pseudomonas; Teredinibacter; Stenotrophomonas; Xanthomonas; Oceanimonas; and Acinetobacter.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 8.”
- “Gram( ⁇ ) Proteobacteria Subgroup 8” is defined as the group of Proteobacteria of the following genera: Brevundimonas; Blastomonas; Sphingomonas; Burkholderia; Ralstonia; Acidovorax; Hydrogenophaga; Pseudomonas; Stenotrophomonas; Xanthomonas; Oceanimonas; and Acinetobacter.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 9.”
- “Gram( ⁇ ) Proteobacteria Subgroup 9” is defined as the group of Proteobacteria of the following genera: Brevundimonas; Burkholderia; Ralstonia; Acidovorax; Hydrogenophaga; Pseudomonas; Stenotrophomonas; Oceanimonas; and Acinetobacter.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 10.”
- “Gram( ⁇ ) Proteobacteria Subgroup 10” is defined as the group of Proteobacteria of the following genera: Burkholderia; Ralstonia; Pseudomonas; Stenotrophomonas; Xanthomonas; and Acinetobacter.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 11.”
- “Gram( ⁇ ) Proteobacteria Subgroup 11” is defined as the group of Proteobacteria of the genera: Pseudomonas; Stenotrophomonas; Xanthomonas; and Acinetobacter.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 12.”
- “Gram( ⁇ ) Proteobacteria Subgroup 12” is defined as the group of Proteobacteria of the following genera: Burkholderia; Ralstonia; Pseudomonas.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 13.”
- “Gram( ⁇ ) Proteobacteria Subgroup 13” is defined as the group of Proteobacteria of the following genera: Burkholderia; Raistonia; Pseudomonas; Xanthomonas; and Acinetobacter.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 14.”
- “Gram( ⁇ ) Proteobacteria Subgroup 14” is defined as the group of Proteobacteria of the following genera: Pseudomonas and Xanthomonas.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 15.”
- “Gram( ⁇ ) Proteobacteria Subgroup 15” is defined as the group of Proteobacteria of the genus Pseudomonas.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 16.”
- “Gram( ⁇ ) Proteobacteria Subgroup 16” is defined as the group of Proteobacteria of the following Pseudomonas species (with the ATCC or other deposit numbers of exemplary strain(s) shown in parenthesis): Pseudomonas abietaniphila (ATCC 700689); Pseudomonas aeruginosa (ATCC 10145); Pseudomonas alcaligenes (ATCC 14909); Pseudomonas anguilliseptica (ATCC 33660); Pseudomonas citronellolis (ATCC 13674); Pseudomonas flavescens (ATCC 51555); Pseudomonas mendocina (ATCC 25411); Pseudomonas nitroreducens (ATCC 33634);
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 17.”
- “Gram( ⁇ ) Proteobacteria Subgroup 17” is defined as the group of Proteobacteria known in the art as the “fluorescent Pseudomonads” including those belonging, e.g.
- Pseudomonas species Pseudomonas azotoformans; Pseudomonas brenneri; Pseudomonas cedrella; Pseudomonas corrugata; Pseudomonas extremorientalis; Pseudomonas fluorescens; Pseudomonas gessardii; Pseudomonas libanensis; Pseudomonas mandelii; Pseudomonas marginalis; Pseudomonas migulae; Pseudomonas mucidolens; Pseudomonas orientalis; Pseudomonas rhodesiae; Pseudomonas synxantha; Pseudomonas tolaasii; and Pseudomonas veronii.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 18.”
- “Gram( ⁇ ) Proteobacteria Subgroup 18” is defined as the group of all subspecies, varieties, strains, and other sub-special units of the species Pseudomonas fluorescens, including those belonging, e.g., to the following (with the ATCC or other deposit numbers of exemplary strain(s) shown in parenthesis): Pseudomonas fluorescens biotype A, also called biovar 1 or biovar I (ATCC 13525); Pseudomonas fluorescens biotype B, also called biovar 2 or biovar II (ATCC 17816); Pseudomonas fluorescens biotype C, also called biovar 3 or biovar III (ATCC 17400); Pseudomonas fluorescens biotype F, also called biovar 4 or biovar IV (ATCC 12983); Pseudomona
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 19.”
- “Gram( ⁇ ) Proteobacteria Subgroup 19” is defined as the group of all strains of Pseudomonas fluorescens biotype A.
- a particularly preferred strain of this biotype is P. fluorescens strain MB101 (see U.S. Pat. No. 5,169,760 to Wilcox), and derivatives thereof.
- the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 1.” In a particularly preferred embodiment, the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 2.” In a particularly preferred embodiment, the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 3.” In a particularly preferred embodiment, the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 5.” In a particularly preferred embodiment, the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 7.” In a particularly preferred embodiment, the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 12.” In a particularly preferred embodiment, the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 15.” In a particularly preferred embodiment, the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 17.” In a particularly preferred embodiment, the bacteria are selected from “Gram( ⁇ ) Proteobacteria Subgroup 1.
- An expression system according to the present invention can be cultured in any fermentation format.
- batch, fed-batch, semi-continuous, and continuous fermentation modes of any volume may be employed herein.
- growth, culturing, and/or fermentation of the host cells is performed within a temperature range permitting survival of the host cells, preferably a temperature within the range of about 4° C. to about 55° C., inclusive.
- a temperature range permitting survival of the host cells preferably a temperature within the range of about 4° C. to about 55° C., inclusive.
- growth is used to indicate both biological states of active cell division and/or enlargement, as well as biological states in which a non-dividing and/or non-enlarging cell is being metabolically sustained, the latter use of the term “growth” being synonymous with the term “maintenance.”
- growth “under conditions permitting expression” when used in regard to the bacterial host cells and expression systems of the present invention is defined herein to mean: (1) growth of the recombinant bacterial host cells per se, where the promoter used in the control sequence operably linked to the coding sequence is a constitutive promoter; and (2) where the promoter used in the control sequence operably linked to the coding sequence is a regulated promoter, (a) growth of the recombinant bacterial host cells in the presence of (i.e. in contact with) an inducer thereof, and (b) growth of the recombinant bacterial host cells in the absence of an inducer thereof, followed by addition of such an inducer to the system, thereby causing contact between the cell and the inducer.
- the resulting gene product(s) and/or secondary products (e.g., metabolites) resulting from expression of the gene product(s) can be separated, isolated, and/or purified using any recovery and/or purification methods known in the art as useful for such a product, e.g., a protein, nucleic acid, or other molecule.
- a product e.g., a protein, nucleic acid, or other molecule.
- the host cells themselves can be used, e.g., in whole cell bioreactors or in other applications.
- Plasmid Tandem Promoter Constructs Plasmid Promoter or Activator-Promoter Designation Sequence Identity Construct Description pDOW1057 SEQ ID NO:13 AntR-Ptandem::lacZ pDOW1111 SEQ ID NO:13 N1085–N1541 Pant311-Pben278::lacZ pDOW1107 SEQ ID NO:13 N1–N1518 with AntR-Ptandem[Pben88( ⁇ 10wt)]::lacZ deletion of g1508 pDOW1108 SEQ ID NO:13 N1–N1518 with AntR-Ptandem[Pben88( ⁇ 10con)]::lacZ deletion of g1508 and substitution of Pben native ⁇ 10 ‘tacggt’ 1498–1503 by ‘tataat’ pDOW1109 SEQ ID NO:13 N1–N1518 with AntR-Ptandem[Pben88( ⁇ 10benAc)]::lacZ
- oligonucleotides listed in Table 7 are utilized in the following examples.
- P. fluorescens MB214 is a derivative of strain MB101 (a wild-type prototrophic P. fluorescens biovar A).
- MB214 had been prepared by integrating the E. coli laclZYA operon (deleted of the lacZ promoter region) into the chromosome of strain MB 101 to provide a host cell wherein the lac promoter and its derivatives can be regulated by lactose or IPTG to drive inducible expression of transgenes of interest.
- the MB101 strain is Lac( ⁇ ) whereas the MB214 strain is Lac(+).
- an “anthranilate” inducer means sodium anthranilate
- a “benzoate” inducer means sodium benzoate
- E. coli Transformations of E. coli were performed as per the manufacturer's protocol, using strain JM109 chemically competent cells from Promega (Madison, Wis.).
- P. fluorescens Electroporation of P. fluorescens was performed by subculturing 1 mL of an overnight culture (grown in rich medium; the present examples used Luria-Bertni Broth, Miller (ie. LB Broth, Miller) (available from Difco, Detroit, Mich.) into 50 mL LB Broth, Miller and incubating at 30° C. with shaking until an A600 measurement falls within the range of 0.4-0.6. The resulting cells were washed twice with 50 mL cold ddH20 and resuspend in 1 mL cold ddH20.
- Cell growth for induction Strains of interest were grown overnight (at 30° C. with shaking at 250 rpm) in 1 ⁇ M9 minimal salts medium (diluted from a 5 ⁇ preparation purchased from Fisher Scientific, Pittsburgh, Pa.) supplemented with 0.5% or 1% (w/v) glucose, 1 mM MgSO 4 , and trace elements (for trace elements, the present examples used a solution containing salts of sodium, magnesium, manganese, iron, and cobalt, all at less than 0.5 mg/mL final concentration). Strains were then subcultured 1:4 in the same medium to a volume of 10 or 20 mL and then induced with 0-10 mM concentrations of anthranilate or benzoate, as indicated.
- 1 ⁇ M9 minimal salts medium diluted from a 5 ⁇ preparation purchased from Fisher Scientific, Pittsburgh, Pa.
- trace elements for trace elements, the present examples used a solution containing salts of sodium, magnesium, manganese, iron, and cobalt, all at less than 0.5 mg/mL final
- E. coli cells containing a plasmid of interest were grown overnight in 50-200 mL of LB Broth, Miller, supplemented with 15 ⁇ g/ML tetracycline or 100 ⁇ g/mL ampicillin (depending on the plasmid to be isolated) at 37° C., with shaking at 250 rpm.
- Plasmids preparations were performed using the NUCLEOSPIN kit (plasmid DNA purification “miniprep” kit for use with culture volumes up to 5 mL; available from BD Biosciences Clontech, Palo Alto, Calif.) or the NUCLEOBOND kit (plasmid DNA purification “midiprep” kit for use with culture volumes up to 200 ml; available from BD Biosciences Clontech, Palo Alto, Calif.).
- Strains of interest were grown overnight at 30° C. in 1 ⁇ M9 medium supplemented with 0.5% or 1% (w/v) glucose, 1 mM MgSO 4 , and 5L/L trace elements (as described above), and optionally tetracycline at 15 ug/mL. These were then subcultured 1:4 or 1:5 in the same medium and then induced with indicated concentrations of anthranilate, benzoate, or other inducer, for a desired amount of time (e.g., for 2, 4, 6, 8, 12, or 24 hours, or overnight). Samples were taken at indicated times and those samples were assayed for reporter gene activity. Results are reported at time points taken at a given number of hours post-induction; time points are indicated by either a numeral for the number of hours, and in some cases this number is immediately preceded by the letter “I” indicating post-induction.
- PCR conditions were as follows: 94° C. for 3 min.; 30 cycles of 30 sec. at 94° C., 30 sec. at 50° C., and 90 sec. at 72° C.; hold at 4° C.
- PCR products were purified using MICROCON YM-100 or MICROCON-PCR columns (nucleic acid purification columns, Millipore Corp., Bedford, Mass.) according to the manufacturer's instructions for AMICON devices.
- Products were digested with BamHI and HindIII (New England BioLabs) in 1 ⁇ NEBUFFER BAMH I+BSA (BamH I restriction endonuclease buffer, available from New England BioLabs) and purified by gel extraction using either QIAEX II (gel extraction kit, from Qiagen, Valencia, Calif.), for fragments of 300 bp and smaller, or PREP-A-GENE (DNA purification kit, from Bio-Rad Laboratories), for fragments larger than 300 bp. The fragments were then cloned upstream of the lacZ or phoA reporter gene of pDOW1017 or pDOW1033, respectively.
- QIAEX II gel extraction kit, from Qiagen, Valencia, Calif.
- PREP-A-GENE DNA purification kit, from Bio-Rad Laboratories
- AntA Knock-Out An internal fragment of the antA gene was amplified using primers AntAKO5 (GGAATTCTTCGTGACGATGCG) (SEQ ID NO:16) and AntAKO3 (CGGGATCCGCTCGCGATGCTGC) (SEQ ID NO:17) from P. fluorescens genomic DNA (EcoRI and BamHI sites, respectively, shown in italics).
- the reaction mixture was formed by combining: 5 ⁇ L 10.times.buffer (i.e.
- the buffer supplied by Invitrogen with the Taq polymerase which buffer contained 200 mM Tris-HCl (pH 8.4) and 500 mM KCl), 2.5 ⁇ L 50 mM MgCl 2 , 1 ⁇ L 10 mM dNTPs, 0.5 ⁇ L 100 ⁇ M AntKO3, 0.5 ⁇ L 100 ⁇ M AntKO5, 1 ⁇ L (5 Units/ ⁇ L) Taq polymerase (Invitrogen Corp., Carlsbad, Calif.), 0.5 ⁇ L P. fluorescens MB214 genomic DNA ( ⁇ 50 ng), and 39 ⁇ L ddH 2 O.
- the PCR cycle conditions used were: 2 min. at 96° C.; 30 cycles of 30 sec.
- the resulting PCR product was cloned into a plasmid unable to replicate in P. fluorescens (a pUC type plasmid was used, though, e.g., pBR type plasmids will also work).
- the resulting plasmid was transformed into electrocompetent P. fluorescens cells, and the transformants were selected with the appropriate antibiotic. Since the plasmid cannot replicate in P. fluorescens , only those bacteria which have the plasmid integrated at the antA locus, resulting in two truncated antA ORFs separated by the plasmid backbone, can be selected.
- transformants were cultured in M9 medium+1.0% glucose, 5 mM anthranilate, at 30° C. with shaking for 24 hours, and culture supernatants were analyzed by HPLC for anthranilate concentration.
- the plasmid pDOW 1139 was constructed to facilitate deletion of the benAB genes as follows.
- the 3′ portion of the benR gene and the 5′ portion of the benC gene were amplified using P. fluorescens MB214 genomic DNA as template.
- the benR region was amplified using primers H3 — 5′benAKOclean and BenKOmega.
- the benC region was amplified using primers H3 — 3′BenBKOclean and InvbenKOmega. For both reactions, the cycling conditions were 95° C.
- the expected 1.1 kb fragment was gel purified using QIAEX II (Qiagen) and cloned into SrfI-digested plasmid DNA to form plasmid, pDOW1139.
- pDOW1139 was then transformed into P. fluorescens ).
- Transformants were selected by plating on LB medium with tetracycline for selection. Since the plasmid could not replicate in P. fluorescens , colonies resistant to tetracycline arose from the plasmid being integrated into the chromosome. The site of integration of the plasmid was analyzed by PCR.
- the resulting products were cloned into the pCR2.1 vector (form Invitrogen Corp.) and transformed into E. coli Top10 cells. Transformants were screened for insert by colony PCR using the above primers/conditions, and the positive clones were further confirmed by DNA sequencing. The resulting plasmids were then used to insertionally inactivate the corresponding chromosomal ORFs. DNA samples were prepared using a NucLEoBoND plasmid midiprep kit (from Clontech Corp.) and 4 ⁇ g of plasmid DNA was transformed into P. fluorescens strain MB101. The resulting transformants were screened again by colony PCR.
- PCR reaction cycle conditions were: 94° C.
- MB101 genomic DNA and pDOW1125 were used as controls. Inactivation of this BenR gene resulted in inability of the knock-out host cells to activate transgenic Pben-reporter gene constructs, as well as inability to metabolize benzoate.
- Oligonucleotides used for site directed mutagenesis are found listed among SEQ ID NOs:16-41. Construction of the Pben ⁇ 10 promoter mutants was conducted as follows. The plasmid pDOW1022 was used as template for polymerase chain reaction (PCR) with 1 uM primer benL278 and 1 ⁇ M of bambenconshort, bambenwtshort, or bambenAcshort. Recombinant Taq polymerase (from Invitrogen Corp.) was used according to the manufacturer's instructions. The reaction cycling protocol was 94° C.
- Pant-10 promoter mutants were conducted as follows.
- the plasmid pDOW1039 was used as template for PCR with 1 uM primer 3′ Antactiv and 1 uM of primer bamantwtshort or bamantconshort.
- Recombinant Taq polymerase (from Invitrogen Corp.) was used according to the manufacturer's instructions.
- the reaction cycling protocol was 94° C. for 2 min.; (30 sec at 94° C., 30 sec at 60° C., and 30 sec at 72° C.) for 25 times; then 72° C. for 7 min.
- plasmids pDOW1095 and 1098 contain antR-Pant::phoA fusions, with variations of the ⁇ 10 region of the promoter.
- Cloned inserts were sequenced using ABI PRISM BIGDYE V2.0 or V3.0 DNA sequencing kit from (Applied Biosystems, Inc., Foster City, Calif.) as follows: 4 ⁇ L of premix (containing buffer, Taq polymerase, and dye terminators, as supplied in the Applied Biosystems kit), 50 fmol of plasmid template, 3.2-5 pmol of desired sequencing primer, and 2 ⁇ L of 5 ⁇ buffer (as supplied in the Applied Biosystems kit) were combined (to a fiaal volume of 20 ⁇ L). The PCR cycling profile used was: 45 cycles of 30 sec. at 95° C., 20 sec. at 50° C., and 4 min. at 60° C.
- Samples were purified using SEPHADEX G-50 (a bead-form, dextran gel for chromatographic purification of nucleic acids, from Sigma Chemical Company, St. Louis, Mo.), dried, resuspended in formamide, and then run on an AB13100 automated DNA sequencer (a 16 capillary array, automated DNA sequencer, from Applied Biosystems, Inc.).
- SEPHADEX G-50 a bead-form, dextran gel for chromatographic purification of nucleic acids, from Sigma Chemical Company, St. Louis, Mo.
- RNA Isolation An RNA isolation procedure was followed in order to identify the transcription start sites under the control of the P. fluorescens Pant and Pben promoters. The procedure used is as follows. An overnight culture of P. fluorescens MB101 carrying the appropriate plasmid was grown in 1 ⁇ M9 medium supplemented with 1% glucose (w/v), 1 mM MgSO 4 , and trace elements (as described above) was subcultured 1:4 (v/v) in the same medium to a final volume of 50 mL. The culture was induced with 5 mM benzoate or anthranilate as appropriate for 8 or 24 hours.
- RNA concentration was determined using RIBOGREEN (RNA quantitation kit, from Molecular Probes, Inc., Eugene, Oreg.), following the manufacturer's protocol.
- Primer Labeling This was performed by mixing 1 ⁇ L 10 ⁇ M primer (either lacZPE, GGATGTGCTGCAAGGC (SEQ ID NO:18), or lacZPE2, GTAACCATGGTCATCGC (SEQ ID NO:19)), 1 ⁇ L 10 ⁇ T4 polynucleotide kinase buffer (700 mM Tris-HCl (pH 7.6), 100 mM MgCl 2 , 50 mM dithiothreitol (DTT)), 5 ⁇ L 32 P- ⁇ ATP (50 ⁇ Ci, Amersham-Pharmacia), 1 ⁇ L T4 kinase (New England BioLabs), and 2 ⁇ L ddH 2 O; and incubating the resulting reaction mixture at 37° C.
- primer either lacZPE, GGATGTGCTGCAAGGC (SEQ ID NO:18), or lacZPE2, GTAACCATGGTCATCGC (SEQ ID NO:19
- Sequencing ladder This was performed according to the protocol that came with the FMOL kit (DNA sequencing kit from Promega Corp.), using 1 picomole (pmol) of the labeled primer described above. Plasmid template used corresponds with that contained in the strain from which RNA was isolated for the extension reaction.
- Primer Extension reaction Primer extension reactions were performed by mixing 10-20 ⁇ g of total RNA with 0.2 pmol primer to yield a final volume of 12 ⁇ L, followed by incubation at 70° C. 10 min. Then, the following were added: 4 ⁇ L 5 ⁇ SUPERSCRIPT II buffer (250 mM Tris-HCl (pH 8.3), 375 mM KCl, 15 mM MgCl 2 , available from Life Technologies, now Invitrogen Corp., Carlsbad, Calif.), 2 ⁇ L 1M DTT, 1 ⁇ L 10 mM dNTPs, and 1 ⁇ L SUPERSCRIPT II (reverse transcriptase, from Life Technologies, now Invitrogen), followed by incubation at 42° C.
- 4 ⁇ L 5 ⁇ SUPERSCRIPT II buffer 250 mM Tris-HCl (pH 8.3), 375 mM KCl, 15 mM MgCl 2 , available from Life Technologies, now Invitrogen Corp.,
- the resulting mixture was treated by either an addition of 5 ⁇ L sequencing stop solution (containing formamide and tracking dye, as supplied in the Promega FMOL kit) or, in those cases where the signal was weak, by: precipitation with 2 ⁇ L 3M sodium acetate/40 ⁇ L 100% ethanol, followed by centrifugation for 10 minutes to pellet suspended matter, drying of the pellet, and resuspension in 4 ⁇ L H 2 O+2 ⁇ L sequencing stop solution.
- the product mixture resulting from the primer extension reaction was then electrophoresed on a LONG RANGER gel (made from 6% pre-mixed gel solution, from Biowhittaker Molecular Applications, Rockland, Me.) containing 8M Urea and 1.2 ⁇ TBE (ie.
- Tris-Borate-EDTA as diluted from 10 ⁇ TBE obtained from Fisher Scientific, Pittsburgh, Pa.
- the gel was dried and exposed to a phosphor screen (from Molecular Dynamics, now Amersham Biosciences, Inc., Piscataway, N.J.) to detect radiolabeled DNA fragment, and imaged on the TYPHOON PHOSPHORIMAGER (Molecular Dynamics, now Amersham Biosciences, Inc., Piscataway, N.J.).
- Primer extension using Thermoscript reverse transcriptase 30 ng total RNA, 1 ⁇ L 0.2 ⁇ M primer, and ddH 2 O to a final volume of 12 ⁇ L were mixed and then incubated at 70° C. for 10 min. To this mixture were added 4 ⁇ L 5 ⁇ cDNA synthesis buffer (250 mM Tris acetate (pH 8.4), 375 mM potassium acetate, 40 mM magnesium acetate), 1 ⁇ L 0.1M DTT, 2 ⁇ L 10 mM dNTPs, 1 ⁇ L THERMOSCRIPT RT (reverse transcriptase from Invitrogen Corp.), and the resulting mixture was incubated at 55° C. for 1 hour.
- 5 ⁇ cDNA synthesis buffer 250 mM Tris acetate (pH 8.4), 375 mM potassium acetate, 40 mM magnesium acetate
- 1 ⁇ L 0.1M DTT 2 ⁇ L 10 mM dNTPs
- reaction product was precipitated, dried, and resuspended in 4 ⁇ L ddH2O+2 ⁇ L stop solution (described above). All reactions were heated at 70° C. for 2 minutes immediately before being loaded onto the gel as described above. The gel was run as described above.
- SIGMA FAST p-nitrophenyl phosphate (PNPP) substrate, from Sigma-Aldrich Corp., St. Louis, Mo.
- PNPP p-nitrophenyl phosphate
- the cell density of each culture providing the 5 ⁇ L of cells used in each tested sample was read at A600 (i.e. the cell cultures were read in a 96 well plate). The value of A410/(0.1 * A600) was then calculated to express alkaline phosphatase activity/cell.
- Benzoate is an inexpensive, essentially nontoxic compound, making it an ideal candidate for an inducer.
- a 509 bp region of P. fluorescens DNA was cloned. This region was found located upstream of a putative benA translational start site ( FIG. 5 ), which was part of the coding sequence of a subunit of benzoate dioxygenase. The cloned region was found to contain a benzoate-inducible promoter (Pben), and was named “Pben509”.
- Benzoate-inducible promoter activity was tested by fusing the DNA fragment containing the putative promoter sequence of Pben509, or of Pben278 (described below), upstream of an easily assayable reporter gene (i.e. either lacZ, which encodes ⁇ -galactosidase and was used as the chief reporter gene, orphoA).
- an easily assayable reporter gene i.e. either lacZ, which encodes ⁇ -galactosidase and was used as the chief reporter gene, orphoA.
- lacZ which encodes ⁇ -galactosidase and was used as the chief reporter gene, orphoA
- the resulting plasmid was transformed into P. fluorescens MB101.
- induction of ⁇ -galactosidase activity was measured using the chromogenic substrate o-nitrophenol- ⁇ -D-galactopyranoside (ONPG) (see FIG. 6 ).
- Both Pben 509 and Pben278 promoter activity was found to be inhibited during fermentation, due to the presence of a small, but significant concentration of glucose. Thus, these promoters are catabolite-repressed.
- Anthranilate like benzoate, is an inexpensive low toxic compound that can be utilized by P. fluorescens , making it an ideal compound to investigate as an inducer.
- Four promoter constructs have been cloned upstream of either a lacZ or phoA reporter and have been found to possess similar activity upon induction with anthranilate: Pant713, Pant705, Pant311, and Pant+antR coding sequence (CDS) ( FIG. 7 ).
- Pant713 and Pant705 have the same 5′ end, but Pant713 contains the predicted ribosome binding site of the antA gene, whereas Pant705 does not (see the underlined CCTCC, nucleotides 1299 through 1303 of SEQ ID NO:7, in the final octamer shown for Pant713).
- the Pben713 construct was truncated on the 5′ terminus to 311 base pairs (bp) The Pant311 construct was found to retain activity similar to that of Pant713 (data not shown).
- Expansion of the promoter clone to include the transcriptional activator gene 5′ of the antA open reading frame (ORF) increased expression levels of the lacZ fusion.
- the transcriptional start site was mapped to 31 nucleotides upstream of the predicted antA translational start site, for both Pant713 and the expanded clone that includes the transcriptional activator AntR (data not shown; also see FIG. 7 ).
- the presence of antR in multi-copy with the lacZ fusion was found to enable faster and stronger induction (see FIG. 8 ).
- FIG. 8 demonstrates a substantial difference in the rates of induction and the maximum levels of induction achieved for each of these promoters during the 24 hour time course of the study.
- pDOW1029 contains the Pant713 promoter, which lacks the antR coding sequence;
- pDOW1035 contains the full activator CDS.
- the P fluorescens host cell used contains an actively expressed, chromosomal copy of the antR CDS.
- results shown in FIG. 8 for pDOW1029 are for a system in which the antR gene is present in a single copy, while the results for pDOW1035 represent a two-copy system.
- These results demonstrate that the presence of an extra copy of the antR gene dramatically improves both the rate and level of response of the Pant promoter.
- Such improved expression can alternatively be obtained, or further enhanced, by driving antR expression with a very strong promoter.
- Improved induction/expression can also be obtained, as described below, by using a host cell in which a key gene (e.g., antA) responsible for degradation of the inducer compound (e.g., anthranilate) has been inactivated.
- mutating the activator and/or promoter sequences could also enhance the activator/promoter interaction and thereby allow for more improved anthranilate-inducible expression by Pant.
- the anthranilate promoter was also found to be inducible by anthranilate analogs, including the halo-substituted anthranilic acid derivatives: 3-chloro-, 4-chloro-, 5-chloro- and 6-chloro-anthranilate.
- 6-chloroanthranilate is found to act as a gratuitous inducer of anthranilate metabolism, i.e. it is not metabolized by P. fluorescens yet induces expression from the anthranilate promoter.
- 6-chloroanthranilate was found to induce the Pant713 and antR/Pant constructs ( FIG. 8 ). Taken together, these results indicate that anthranilate itself induces the metabolic pathway; and that it is possible to utilize substituted anthranilate compounds as gratuitous inducers as an alternative to inactivating the anthranilate metabolic pathway of the host organism.
- the relative strength of the Pant promoter with multi-copy antR was found to be approximately 1 ⁇ 5 that of the Pben278 promoter.
- the activity of the Pant promoter was not inhibited during fermentation
- a fusion of these two promoters was created by linking them together, as shown in SEQ ID NO:3, i.e. by cloning a fragment antR and Pant, upstream of the Pben278 promoter fused to lacZ.
- the Pben509 promoter was subjected to mutagenesis by error prone PCR. Mutants were screened for improved activity following induction with 10 mM benzoate at the shake flask scale. The mutants identified showed approximately 2-fold improvement over the wild type promoter ( FIG. 10 ). Positive hits were re-transformed into P. fluorescens and re-tested to ensure that the improved activity was in fact due to the new construct.
- FIG. 11 Sequence analysis ( FIG. 11 ) revealed one change in mutant 2d3 and two changes in mutant 21b5. As illustrated in the attached figure, the mutation in isolate 2d3 and one of the mutations in 21b5 fall within the coding region of the upstream ORF. This region is not contained within in the Pben278 construct. The fact that these mutations were isolated in improved promoter mutants indicates that upstream regions may affect transcription, although they are not necessary for activated transcription. The second mutation identified in 21b5 is located five base pairs upstream of the transcriptional start site.
- the native Pben predicted ⁇ 10 region was mutated in an attempt to improve promoter activity.
- the promoter itself was truncated to 88 bp, and three derivatives of the ⁇ 10 were constructed: wild type (TACGGTT, SEQ ID NO:44, consensus (TATAAT, SEQ ID NO:45), and Acinetobacter (Ac) Pben ⁇ 10 (TAAGGT, SEQ ID NO:46), as described in Materials and Methods.
- the primers were constructed such that one bp (G:C) upstream of the previously identified transcriptional start site was removed and 9 bp downstream of the previously identified transcriptional start site are included. These promoters were fused to the phoA reporter gene and tested for activity in P.
- FIG. 14 shows that the truncation of Pben promoter to 88 bp is sufficient to confer benzoate-activated expression, although altering the ⁇ 10 region either to the consensus TATAAT or to the ⁇ 10 sequence of the Acinetobacter Pben promoter did not appear to significantly improve benzoate induced promoter activity.
- FIG. 15 shows that, following induction with anthranilate, the 3′ truncation of the promoter to 289 bp did not affect activity (pDOW1095).
- the tandem promoter having the sequence as shown in pDOW1057 was mutated in the Pben ⁇ 10 region as follows to construct mutant Ptandem promoters.
- the benAB gene knock-out strain of P. fluorescens was further characterized.
- the benA and benB genes code for the large and small subunits of benzoate 1, 2 dioxygenase, respectively.
- Two isolated of the benAB knock-out strain were further tested for the ability to metabolize benzoate as follows. Cells were grown in LB-proline-uracil to high density; benzoate was then added to the cultures to a final concentration of ⁇ 5 mM before they were returned to incubate for 24 hr.
- a DNA fragment containing the BenR ORF upstream of benA along with Pben promoter was amplified from P. fluorescens MB214 genomic DNA using primers Benact5′ and Bambenconshort under the following conditions: 94° C. for 1 min; (94° C., 1 min; 50° C., 30 sec; 72° C., 90 sec) for 30 cycles; then 72° C. for 10 min, and 4° C. hold.
- the PCR product was ligated into the pCR2.1 vector, and the sequence verified.
- the insert fragment was digested with PmeI and BamHI, and ligated to pDOW1033.
- the resulting plasmid was stocked as pDOW1090.
- the same promoter construct was fused to the lacZ reporter by digesting pDOW1090 with BamHI and XhoI to remove the phoA reporter, and replacing it with the 3 Kb BamI-HXhoI fragment of pDOW1035, containing the lacZ reporter gene.
- the pDOW1108 construct is “leaky”, in that significant expression occurs prior to addition of the inducer, this should not present a large problem for its use in protein expression.
- Pben is active in the benAB knock-out strain
- use of such a knock-out strain will improve benzoate-induced promoter activity for Pben, as well as Ptandem.
- induction of the tandem promoter construct pDOW1057 with anthranilate is improved in a strain carrying and insertionally inactivated chromosomal ant4 gene, improved anthranilate-induced promoter activity will be enhanced for Pant, as well as Ptandem.
- anthranilate- and benzoate-inducible promoters have now been developed for use in bacterial expression systems. These promoters have been found to permit tight regulation of transcription and are inducible with low-cost compounds such as benzoate and anthranilate; the presence of antR in multi-copy also now has been found to significantly improve the activity of the Pant promoter.
- a new type of tandem promoters has now been developed for use in bacterial expression systems, exemplified by Pant-Pben tandem promoters that have been found to exhibit increased levels of anthranilate-induced gene expression, over Pant itself; were found to be benzoate-inducible, i.e.
- both the Pant promoter (with antR) and the tandem promoter constructs exhibit anthnnilate-inducible gene expression under fermentation-scale conditions (e.g., at the 20 L scale); the tandem promoter constructs also exhibits benzoate inducible gene expresion under fermentations-scale condiitons.
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DE102008052529A1 (de) * | 2008-10-21 | 2010-04-22 | Henkel Ag & Co. Kgaa | Expressionsverstärkte Nukleinsäuren |
AU2010247938B2 (en) | 2009-05-11 | 2016-02-18 | Pelican Technology Holdings, Inc. | Production of recombinant proteins utilizing non-antibiotic selection methods and the incorporation of non-natural amino acids therein |
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AU2015276994A1 (en) | 2014-06-18 | 2016-12-01 | Calysta, Inc. | Nucleic acids and vectors for use with methanotrophic bacteria |
EP3701035A4 (en) * | 2017-10-26 | 2021-05-26 | Noroo IC Co., Ltd. | PREPARATION AND SEPARATION OF 3-HYDROXYPROPIONIC ACID |
US11566250B2 (en) | 2017-10-26 | 2023-01-31 | Noroo Ic Co., Ltd. | Production and separation of 3-hydroxypropionic acid |
CN109486847B (zh) * | 2018-12-17 | 2021-03-02 | 江南大学 | 基于人工串联启动子的枯草芽孢杆菌高效诱导表达系统 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6415739A (en) | 1987-07-09 | 1989-01-19 | Konishiroku Photo Ind | Processing of silver halide color photographic sensitive material |
EP0345155A1 (en) | 1988-05-31 | 1989-12-06 | Mitsubishi Kasei Corporation | Process for producing natural human apolipoprotein e-like proteins |
JPH0284195A (ja) | 1988-05-31 | 1990-03-26 | Mitsubishi Kasei Corp | 天然型ヒトアポリポプロテインe様蛋白質の産生方法 |
US5593860A (en) | 1987-08-14 | 1997-01-14 | Bio-Technology General Corp. | Expression plasmids containing the deo promoter, and bacterial hosts containing the plasmids |
WO1998020111A1 (en) | 1996-11-08 | 1998-05-14 | Cytel Corporation | Improved expression vectors |
WO1999043835A2 (en) | 1998-02-26 | 1999-09-02 | Novo Nordisk Biotech, Inc. | Methods for producing a polypeptide in a bacillus cell |
-
2003
- 2003-07-03 DE DE60325611T patent/DE60325611D1/de not_active Expired - Lifetime
- 2003-07-03 AT AT03763112T patent/ATE419265T1/de not_active IP Right Cessation
- 2003-07-03 CA CA002491056A patent/CA2491056A1/en not_active Abandoned
- 2003-07-03 AU AU2003256365A patent/AU2003256365B2/en not_active Ceased
- 2003-07-03 CN CN038206595A patent/CN1678624B/zh not_active Expired - Fee Related
- 2003-07-03 JP JP2004519773A patent/JP2006506049A/ja active Pending
- 2003-07-03 EP EP03763112A patent/EP1539794B1/en not_active Expired - Lifetime
- 2003-07-03 WO PCT/US2003/020840 patent/WO2004005221A2/en active Application Filing
-
2005
- 2005-01-03 US US11/028,156 patent/US7794972B2/en not_active Expired - Fee Related
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6415739A (en) | 1987-07-09 | 1989-01-19 | Konishiroku Photo Ind | Processing of silver halide color photographic sensitive material |
US5593860A (en) | 1987-08-14 | 1997-01-14 | Bio-Technology General Corp. | Expression plasmids containing the deo promoter, and bacterial hosts containing the plasmids |
EP0345155A1 (en) | 1988-05-31 | 1989-12-06 | Mitsubishi Kasei Corporation | Process for producing natural human apolipoprotein e-like proteins |
JPH0284195A (ja) | 1988-05-31 | 1990-03-26 | Mitsubishi Kasei Corp | 天然型ヒトアポリポプロテインe様蛋白質の産生方法 |
WO1998020111A1 (en) | 1996-11-08 | 1998-05-14 | Cytel Corporation | Improved expression vectors |
WO1999043835A2 (en) | 1998-02-26 | 1999-09-02 | Novo Nordisk Biotech, Inc. | Methods for producing a polypeptide in a bacillus cell |
JP2002504379A (ja) | 1998-02-26 | 2002-02-12 | ノボザイムス バイオテック,インコーポレイティド | バチルス細胞内でのポリペプチドの製法 |
Non-Patent Citations (28)
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016089782A1 (en) | 2014-12-01 | 2016-06-09 | Pfenex Inc. | Fusion partners for peptide production |
US10118956B2 (en) | 2014-12-01 | 2018-11-06 | Pfenex Inc. | Fusion partners for peptide production |
US10981968B2 (en) | 2014-12-01 | 2021-04-20 | Pfenex Inc. | Fusion partners for peptide production |
Also Published As
Publication number | Publication date |
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EP1539794A4 (en) | 2005-12-28 |
EP1539794B1 (en) | 2008-12-31 |
AU2003256365A1 (en) | 2004-01-23 |
WO2004005221A2 (en) | 2004-01-15 |
CN1678624B (zh) | 2011-10-26 |
CN1678624A (zh) | 2005-10-05 |
JP2006506049A (ja) | 2006-02-23 |
WO2004005221A3 (en) | 2004-12-02 |
US20050202544A1 (en) | 2005-09-15 |
DE60325611D1 (de) | 2009-02-12 |
ATE419265T1 (de) | 2009-01-15 |
EP1539794A2 (en) | 2005-06-15 |
CA2491056A1 (en) | 2004-01-15 |
AU2003256365B2 (en) | 2010-02-18 |
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